Added Rugged, converted existing Grit code

Description incomplete, coming :soon:  

Here's a [Working demo](http://glittergallery-ropaku.rhcloud.com/) and a [Test Project](http://glittergallery-ropaku.rhcloud.com/rohitpaulk/TestProject1) that I set up.
Auch.

Here's what I did: 
* Create new project -> takes me to project show page
* Log -> works fine now
* Add files -> takes me to newfile page
* Upload file -> throws following error
![rugged](https://cloud.githubusercontent.com/assets/3149580/3278929/42509526-f3dd-11e3-91ae-c87ebd3a906d.png)
* On the live console, I do: 
```
>> headcommit
=> "c1b740f631097cafc413daa8385c1c5b2ddeeba6"
>> headtree
=> nil
>> barerepo.lookup(headcommit.tree_id)
!! #<NoMethodError: undefined method `tree_id' for "c1b740f631097cafc413daa8385c1c5b2ddeeba6":String>
>> barerepo.lookup(headcommit)
=> #<Rugged::Commit:50287800 {message: "Add new file drawing.svg.", tree: #<Rugged::Tree:50287640 {oid: a31a6ca26472fc661e4dc2d77184d09aee728934}>
  <"drawing.svg" 67a54c9d403489cdae6115c18bed7a4f6591bc1d>
, parents: []}>
>> barerepo.lookup(headcommit.tree)
!! #<NoMethodError: undefined method `tree' for "c1b740f631097cafc413daa8385c1c5b2ddeeba6":String>
>> barerepo.lookup(headcommit).tree
=> #<Rugged::Tree:52166360 {oid: a31a6ca26472fc661e4dc2d77184d09aee728934}>
  <"drawing.svg" 67a54c9d403489cdae6115c18bed7a4f6591bc1d>
>> barerepo.lookup(headcommit).tree.oid
=> "a31a6ca26472fc661e4dc2d77184d09aee728934"
```