Update libgit2sharp to v0.18.1
Use libgit2sharp to find commits to checkin
Adapt FindParentCommits() to return nothing when commits are not parents
Unit test
Expose a BatchSize option...
Merge branch 'rcheckin_with_libgit2sharp' into all2
Change call to CreateCommit() because old was obsolete
Merge branch 'batch_size_option' into all2
Merge branch 'fix-workspace-conflict' into all2