Fixed NPE in NumberSelectScreen

Whoops, should have switched and done this fix here, then merged to
story.  There might be a conflict now, but it's the same fix.
Merge branch 'master' of https://github.com/thomaswp/tuxblocks
Update TODO.md
Removed Tutorial button, added Story Mode
Preliminary Story Screen and State
Some button stuff

And making some classes default.
Merge remote-tracking branch 'origin/story' into story_new_gui
Added support for multiple triggers and an else
Loading in actual tutorial text
Exclude .git files in open resource
Story mode opens in the game

FSMTutorial seems to be off to a good start
Tutorial with all but "excellent" detection
Tutorial0 can detect "good" tower placement
Merge remote-tracking branch 'origin/master' into story_new_gui
Merge remote-tracking branch 'origin/story' into story_new_gui

Conflicts:
	TODO.md
Made Story State in charge of tutorials

Additionally, added in the ability for the tutorial to start waves
We can chain tutorials now
Started making Tutorial1-1
Highlights appear to be working

Also, organized imports
Messing around with highlight appearance

For the first 2 cycles, it pulses a bit faster.  Also, the highlight is
a bit brighter (yellow skewed)