rename shirt to shirt_reorder
WIP shirt type + color selection

This deviates a bit from how shirt stuff was setup before in ubersystem, in Magstock it's based 100% on attendee.amount_extra

Since there are no other badge types, supporter badges, or donations, the only thing that can be in amount_extra is the shirt cost.

Note: that we are adding a new DB field here, attendee.shirt_color which can be 'black' or 'white for tie die'

We'll probably also need to create some kind of report that shows the breakdown of each shirt type.  When doing that, base the shirt counts ONLY on attendee.shirt != 0
fixing admin shirt editing
- shirt_color dropdown had wrong name
- amount_extra: adding back in zero level and re-enabling on the form
fixing admin shirt editing
- error msg when you try and save an invalid shirt combo
- this branch closes #233
Merge branch 'master' into ftr_magstock_shirt_stuff
more pythonic way of doing this
capitolize shirts, add moon bounce.
Merge pull request #263 from EliAndrewC/ftr_magstock_shirt_stuff

Shirt color+type support