Strip Menu now obscures items based on flags_inv

Fixes #1133

I also made it look pretty

![screenshot 2014-05-31 13 42 48](https://cloud.githubusercontent.com/assets/3828067/3139958/219b9998-e8fc-11e3-83e2-05da5fdc7ff0.png) ![screenshot 2014-05-31 13 43 21](https://cloud.githubusercontent.com/assets/3828067/3139959/239847be-e8fc-11e3-8068-bc3d2ab3d261.png)