Ignore case when sorting installed plugins

The installed plugin list puts plugins that start with a lower case letter at the bottom of the list. This ignores the case when rendering.

Before
![screen shot 2014-04-01 at 8 32 56 pm](https://cloud.githubusercontent.com/assets/185091/2577558/3ff6af2c-b981-11e3-9ac6-c3f309698ec2.png)

After
![screen shot 2014-04-01 at 8 33 34 pm](https://cloud.githubusercontent.com/assets/185091/2577552/3279a1e2-b981-11e3-90d0-ca3e6bd4aeb9.png)