Add missing RepositoryOpenExtended arguments
Add missing RepositoryOpenExtended arguments

Fixes #277

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