added migration to set defaults
fixed extra defaults for favicon parameters
changed tactics; now preventing nulls
updated schema again
fixed seeding and app_config factory
deleted config variable setting
added Gemfile.lock
Merge branch 'master' into 947_defaultconfigs

Conflicts:
	Gemfile.lock
	db/schema.rb
	spec/factories/app_configs.rb
Merge pull request #962 from YaleSTC/947_defaultconfigs

resolves #947, defaultconfigs