Strip Menu now obscures items based on flags_inv

Fixes #1133

I also made it look pretty

![screenshot 2014-06-01 22 43 47](https://cloud.githubusercontent.com/assets/3828067/3143936/c5d4bd40-ea10-11e3-82a3-ccb764df20ed.png)
![screenshot 2014-06-01 22 44 02](https://cloud.githubusercontent.com/assets/3828067/3143937/c6db8566-ea10-11e3-9918-a0c50a300c31.png)

I think this needs to be canUseTopic(usr).