Add Roslyn version 3.4.0.1952101 binaries from the vsix (#20)

.. corresponding to the nuget Microsoft.Net.Compilers
3.4.0-beta3-19521-01 .

Version taken from
https://github.com/dotnet/toolset/blob/172f26ddc1dc3c96f14bfcba8519544d30d6d3e2/eng/Versions.props#L36
current HEAD of `release/3.1.1xx` branch.

- Removed these from the vsix:
    - [Content_Types].xml
    - catalog.json
    - extension.vsixmanifest
    - manifest.json
    - Roslyn.Compilers.Extension.* (windows/VS specific)
    - skipped package/* directory

- Edited `csi.rsp` with (matches what we used for 3.3.1):

```
-/r:System
-/r:System.Core
-/r:Microsoft.CSharp
+/r:System.dll
+/r:System.Core.dll
+/r:Microsoft.CSharp.dll
+/r:Facades/System.Runtime.dll
+/r:Facades/netstandard.dll
/u:System
/u:System.IO
/u:System.Collections.Generic
```

13 files changed, 10 insertions, 8 deletions

diff --git a/Microsoft.Net.Compilers/3.4.0/Microsoft.Build.Tasks.CodeAnalysis.dll b/Microsoft.Net.Compilers/3.4.0/Microsoft.Build.Tasks.CodeAnalysis.dll
index 9c77e0f..bd5802a 100644
--- a/Microsoft.Net.Compilers/3.4.0/Microsoft.Build.Tasks.CodeAnalysis.dll
+++ b/Microsoft.Net.Compilers/3.4.0/Microsoft.Build.Tasks.CodeAnalysis.dll
diff --git a/Microsoft.Net.Compilers/3.4.0/Microsoft.CSharp.Core.targets b/Microsoft.Net.Compilers/3.4.0/Microsoft.CSharp.Core.targets
index 86bc96d..ed91b90 100644
--- a/Microsoft.Net.Compilers/3.4.0/Microsoft.CSharp.Core.targets
+++ b/Microsoft.Net.Compilers/3.4.0/Microsoft.CSharp.Core.targets
@@ -3,8 +3,8 @@
 <Project ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <Import Project="Microsoft.Managed.Core.targets"/>
 
-  <PropertyGroup Condition="('$(TargetFrameworkIdentifier)' != '.NETCoreApp' OR '$(TargetFrameworkVersion)' != 'v3.0') AND
-                            ('$(TargetFrameworkIdentifier)' != '.NETStandard' OR '$(TargetFrameworkVersion)' != 'v2.1')">
+  <PropertyGroup Condition="('$(TargetFrameworkIdentifier)' != '.NETCoreApp' OR '$(_TargetFrameworkVersionWithoutV)' &lt; '3.0') AND
+                            ('$(TargetFrameworkIdentifier)' != '.NETStandard' OR '$(_TargetFrameworkVersionWithoutV)' &lt; '2.1')">
     <MaxSupportedLangVersion Condition="'$(MaxSupportedLangVersion)' == ''">7.3</MaxSupportedLangVersion>
     <LangVersion Condition="'$(LangVersion)' == ''">$(MaxSupportedLangVersion)</LangVersion>
   </PropertyGroup>
diff --git a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.CSharp.Scripting.dll b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.CSharp.Scripting.dll
index 9ea02f0..6a0f33a 100644
--- a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.CSharp.Scripting.dll
+++ b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.CSharp.Scripting.dll
diff --git a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.CSharp.dll b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.CSharp.dll
index 98fa740..282d58a 100644
--- a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.CSharp.dll
+++ b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.CSharp.dll
diff --git a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.Scripting.dll b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.Scripting.dll
index db09108..50cd17b 100644
--- a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.Scripting.dll
+++ b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.Scripting.dll
diff --git a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.VisualBasic.dll b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.VisualBasic.dll
index 4f1824c..73e77c6 100644
--- a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.VisualBasic.dll
+++ b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.VisualBasic.dll
diff --git a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.dll b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.dll
index 99d862a..f19a88d 100644
--- a/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.dll
+++ b/Microsoft.Net.Compilers/3.4.0/Microsoft.CodeAnalysis.dll
diff --git a/Microsoft.Net.Compilers/3.4.0/Microsoft.Managed.Core.targets b/Microsoft.Net.Compilers/3.4.0/Microsoft.Managed.Core.targets
index 987f335..c87a659 100644
--- a/Microsoft.Net.Compilers/3.4.0/Microsoft.Managed.Core.targets
+++ b/Microsoft.Net.Compilers/3.4.0/Microsoft.Managed.Core.targets
@@ -55,12 +55,14 @@
     .editorconfig Support
     ========================
     
-    The discovery of .editorconfig files depends on MSBuild features only available in version 16.1 and later. To avoid evaluation errors when
-    running under earlier versions of MSBuild we place the relevant properties and imports in a separate .targets file.
-    
-    TODO: Inline the import when we no longer need to support earlier versions of MSBuild.
     -->
-  <Import Project="Microsoft.Managed.EditorConfig.targets" Condition="$(MSBuildVersion) >= 16.1.0" />
+  <ItemGroup>
+    <_AllDirectoriesAbove Include="@(Compile->GetPathsOfAllDirectoriesAbove())" Condition="'$(DiscoverEditorConfigFiles)' != 'false'" />
+    <!-- Work around a GetPathsOfAllDirectoriesAbove() bug where it can return multiple equivalent paths when the 
+         compilation includes linked files with relative paths - https://github.com/microsoft/msbuild/issues/4392 -->
+    <PotentialEditorConfigFiles Include="@(_AllDirectoriesAbove->'%(FullPath)'->Distinct()->Combine('.editorconfig'))" Condition="'$(DiscoverEditorConfigFiles)' != 'false'" />
+    <EditorConfigFiles Include="@(PotentialEditorConfigFiles->Exists())" Condition="'$(DiscoverEditorConfigFiles)' != 'false'" />
+  </ItemGroup>
 
   <!--
     ========================
diff --git a/Microsoft.Net.Compilers/3.4.0/VBCSCompiler.exe b/Microsoft.Net.Compilers/3.4.0/VBCSCompiler.exe
index d18e416..fd54cdb 100644
--- a/Microsoft.Net.Compilers/3.4.0/VBCSCompiler.exe
+++ b/Microsoft.Net.Compilers/3.4.0/VBCSCompiler.exe
diff --git a/Microsoft.Net.Compilers/3.4.0/csc.exe b/Microsoft.Net.Compilers/3.4.0/csc.exe
index fce70ee..e5a2d23 100644
--- a/Microsoft.Net.Compilers/3.4.0/csc.exe
+++ b/Microsoft.Net.Compilers/3.4.0/csc.exe
diff --git a/Microsoft.Net.Compilers/3.4.0/csi.exe b/Microsoft.Net.Compilers/3.4.0/csi.exe
index ea9cf00..c33bc19 100644
--- a/Microsoft.Net.Compilers/3.4.0/csi.exe
+++ b/Microsoft.Net.Compilers/3.4.0/csi.exe
diff --git a/Microsoft.Net.Compilers/3.4.0/csi.exe.config b/Microsoft.Net.Compilers/3.4.0/csi.exe.config
index f3a0081..23b57c3 100644
--- a/Microsoft.Net.Compilers/3.4.0/csi.exe.config
+++ b/Microsoft.Net.Compilers/3.4.0/csi.exe.config
@@ -2,10 +2,10 @@
 <!-- Copyright (c)  Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information. -->
 <configuration>
   <startup>
-    <AppContextSwitchOverrides value="Switch.System.Security.Cryptography.UseLegacyFipsThrow=false" />
     <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.7.2" />
   </startup>
   <runtime>
+    <AppContextSwitchOverrides value="Switch.System.Security.Cryptography.UseLegacyFipsThrow=false" />
     <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
       <dependentAssembly>
         <assemblyIdentity name="Microsoft.CodeAnalysis.CSharp" publicKeyToken="31bf3856ad364e35" culture="neutral" />
diff --git a/Microsoft.Net.Compilers/3.4.0/vbc.exe b/Microsoft.Net.Compilers/3.4.0/vbc.exe
index 7d5b81d..4668bd3 100644
--- a/Microsoft.Net.Compilers/3.4.0/vbc.exe
+++ b/Microsoft.Net.Compilers/3.4.0/vbc.exe