Issue 206 Step 1: Remove BuildHelper tab completely on front-end

Goal: Achieve consistent UI amongst all project pages. Only the OH project page has this BuildHelper tab.

This task will be a 3-step code removal process:
1. Remove the front-end html/css.
2. Do a south migration to delete any buildhelper data.
3. Finally, remove any .py files in the models and views that mention the buildhelper.

This commit achieves the first step.