Optimize games controller
Handle challenger or challenged player being nil (i.e. player removed from database)
Include player's game count in player partial
Add /player endpoint for getting current player and validating auth token
Allow games returned from the API to be filtered by completion status
Merge branch 'master' of github.com:joshmcarthur/Latter

Conflicts:
	app/controllers/api/v1/games_controller.rb
	app/views/api/v1/games/index.json.jbuilder
	config/routes.rb