Reconcile the changes between the ffi changes upstream with the changes
to libgit2 in the dev branch.
Conflicts:
src/config.c
src/options.c
src/refspec.c
src/remote.c
This moves enough code into python with CFFI to pass the test_remotes
unit tests. There is no credentials support yet.
There is a small change in the return value of Remote.fetch() in that we
now return a TransferProgress object instead of extracting a few values
into a dictionary.
