nicer view for the Abendmensa

detects the studentenwerk's '-----------' entries as a delimiter and shows them as such.

also, even more checks for not existent or blank data.

*in pictures:*


Turns this:

![bildschirmfoto 2013-05-26 um 11 15 28](https://f.cloud.github.com/assets/51182/565177/67f39e5c-c5eb-11e2-8bef-45b40ee0798d.png)

into this:
![bildschirmfoto 2013-05-26 um 11 58 58](https://f.cloud.github.com/assets/51182/565179/741627e0-c5eb-11e2-9f99-f25cfb07cb28.png)