Add libgit2 to repo, better to do it like this since every distro has different (incompatible) versions of this library. Or no version at all!
Make filedigger significantly faster for large directories

By not checking file sizes for all versions until asked for the info by the versionlistmodel.

Also, quite important! Fix wrong "modified" time stamps for files. Bug in generateSubnodes(), was not reading metadata from the metadata stream for all files, needs to be read unconditionally so that later files will match up with the stream.
Add display of file sizes to the version list delegate.
Small fixes to README.md