add 'omniauth-github' gem
initialize github & omniauth
add 'users' table
add proper devise route
add github sign in button
add omniauth logic
Merge remote-tracking branch 'origin/master' into implement_user

Conflicts:
	app/views/layouts/application.html.erb
	config/routes.rb
	db/schema.rb
Merge pull request #2 from Elanice/implement_user

Реализация User