Git integration doesn't work if the open folder in a sub-folder of a git repository

[Tyriar]

Ubuntu 12.04, vscode 0.10.1

The main reason I want this is to get around slow go to file indexing #55 by opening a sub-directory in Chromium so that indexing it doesn't take very long. Traversing the file path upwards to the root directory should be a fairly quick to perform action.

Repro:

1. mkdir -p foo/bar
2. cd foo
3. git init
4. Code bar
5. Open git integration tab

Expected:
Git integration realises that bar is part of the repo

Actual:
Git integration disabled