Use Spree 2-3-stable
Fix features/admin/parts_spec.rb by adding search button

Running this test raised a javascript error that "delayedObserver" was not a
defined function for a jQuery object.  I removed that code and added a search
button that can be clicked in the parts index to display the search results
Fix features/admin/orders_spec by using Font Awesome icon classes

The had old css icon classes that made them invisible and unclickable in the
UI. Thus the failing test
Fix line_item_spec

The expectation that the parts created would be in stock was failing.  I don't
know why this worked before or what changed to make it fail now.  Also not sure
if this is the best way to set up the parts to be "in stock".
Change the other icons to Font Awesome

There should be more feature tests to make sure that these work