Giterminism internals improvements and fixes
Added support for .gitignore into giterminism subsystem.
[giterminism] Optimize listing fs files
Skip file if:
- not accepted by giterminism config
- not changed locally
- ignored by .gitignore
- not inside an unclean submodule repository
[giterminism] Use pathMatcher for matching paths
[path_matcher] Implement StubPathMatcher that always returns false
[git_repo] ListCommitFilesWithGlob: small improvement
The file path does not get into the result if the glob is the file path without patterns