No need for it now since all the threading queries and
scheduling is done via TBB.
Should be no functional changes as all the removed code
is supposed to be unused.
Remove prefix of filenames that is the same as the folder name. This used
to help when #includes were using individual files, but now they are always
relative to the cycles root directory and so the prefixes are redundant.
For patches and branches, git merge and rebase should be able to detect the
renames and move over code to the right file.