Updated the search action.
Fix filtering logic.
Remove SearchActivity completely: it's the wrong metaphor.

Will replace with active filtering with a dialog at the top.

closes #1
Start roughing in the text filter field.
Add new drawables for cancel.
Search is now working, but the field is always displayed.
Added text filtering support (not dynamic, yet).  Hitting the search
button or the menu item shows a text filter dialog above the content
area, which the user can clear (clearing the search) or close, as
needed.

closes #6