mergetools: add description to all diff/merge tools

The output of `git mergetool --tool-help` and `git difftool --tool-help`
only showed the `alias` of each available merge/diff tool.

It is not always obvious what tool these `aliases` end up using (ex:
`opendiff` runs `FileMerge` and `bc` runs `Beyond Compare`).

This commit adds a short description to each of them to help the user
identify the `alias` they want.

Signed-off-by: Fernando Ramos <greenfoo@u92.eu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/mergetools/kompare b/mergetools/kompare
index e8c0bfa678..4ce23dbe8b 100644
--- a/mergetools/kompare
+++ b/mergetools/kompare
@@ -2,10 +2,18 @@ can_merge () {
 	return 1
 }
 
+diff_cmd_help () {
+	echo "Use Kompare (requires a graphical session)"
+}
+
 diff_cmd () {
 	"$merge_tool_path" "$LOCAL" "$REMOTE"
 }
 
+merge_cmd_help () {
+	echo "Use Kompare (requires a graphical session)"
+}
+
 exit_code_trustable () {
 	true
 }