Changes to Turbo Model Thingy

Changes for TMT in order to add more flexible parts to make models  easier to build 
-Added: FlexBox
-Added: FlexTrapezoid

![2013-06-07_23 05 10](https://f.cloud.github.com/assets/3120553/627761/7a9cd17c-d054-11e2-9c27-b3b911c06050.jpg)