libgit2/libgit2sharp — pull request #269 by jamill (2012-12-06 22:35:01+00:00)
Title: Initial push implementation - WIP

## Initial push implementation on top of libgit2.

#### Implementation:
The main push logic is contained in the `Remote` class. I included an entry point in the `Branch` class as well, to facilitate automatic resolution of the upstream remote.

* I only expose the `update_tips` callback on the remote. This is the only callback that I found was actually called during the push operation. I need to investigate if the `progress` callback on the remote is expected to be called.
* I did not yet expose the `git_push_status_foreach` callback.
* tests...

I can include other entry points, but I wanted to put this up for feedback on the general approach and as a starting point for futher discussion on the desired entry points.