Add mysql2 gem and clean up Gemfile
Remove mysql2 gem. Using psql instead.
Update database.yml.example to display sample postgres config
Merge pull request #2 from atstockland/gemfile_cleanup

Add mysql2 gem and clean up Gemfile
changes from Josh gemfile
whitespace
Merge branch 'master' into add_gradable_items_to_ground_lessons

Conflicts:
	Gemfile
	app/views/flights/form_partials/_scenarios.html.erb