Fix translation map issues
The translation map in CMake causes problems with build directories which involve symlinks. The original use case for the translation map is to support
xyz can change based on the login node, but is otherwise the same filesystem).
The fix is to add a translation map entry for this directory iff the source and binary directories both have a shared non-symlink root below any symlinks. If in the process of finding a shared root, a symlink is discovered before finding the root, no translation map entries should be created for those directories. This also makes the translation map a CMake-specific thing rather than it existing in kwsys as it currently does (see this WIP change.
This issue collects other issues into a single place.