Remove completed? method in Game

As it is not currently being used, it is better not to define it.
Add team method to user
Add members method to Team
Correct user permissions
Add participation and contract methods to Team
Clean up indexes
Game completed? method and more permissions
Only put users that can be read in index
Switch to using permissions for games index
Reindent teams/show
Flash messages
Fix path
Page name validation
Add validation for member size
Add warning message on teams form.
Better teams index
Membership validation for user being on same team
Fix members function not working correctly
Prevent problems with accessing methods in NilClass
Make if statement more compact