add git_submodule_recurse_t type
work in progress wrapping git_clone
wrappers for git_cred, git_transfer_progress. don't call nil callbacks.
minor
wip wrapping git_remote
merge latest, cleanup error handling, add thread locks
add push, refine remotes
fix handling of msg to treat empty str as nil
merge with latest
cleanup clone code
clean up clone code
fix return for old go versions / travis
remove strarray wrappers
Merge pull request #61 from jezell/remotes-wip

Cleaned up remotes / clone / add push / fetch