Add unimplemented diff delta/flag values.
Add unimplemented diff delta/flag values.

libgit2/git2go,libgit2/git2go,ezwiebel/git2go,clns/git2go,pks-t/git2go,clns/git2go,clns/git2go,ezwiebel/git2go,pks-t/git2go,ezwiebel/git2go,libgit2/git2go