Update the clone call because of the change of libgi2
Update the clone call because of the change of libgi2

Merge pull request #459 from libgit2/checkout-options: https://github.com/libgit2/objective-git/commit/c0e98a2790865fbf9d9ee63a88360e9507344986

mssun/pass-ios,mssun/passforios,mssun/pass-ios,mssun/passforios,mssun/passforios,mssun/passforios,mssun/passforios