Issue 123: Add unapproved projects filter

Issue #123

- Added the ability to filter projects by approved/unapproved. Changed Approved checkbox to select with options 'any', 'yes', 'no'.
- Adding a custom filter and preserving the order of existing filters
required overriding of the default filters and declaring them manually

![screen shot 2014-01-21 at 9 31 49 pm](https://f.cloud.github.com/assets/85859/1967955/5d671916-82db-11e3-9336-83a1eb7e3d9c.png)