Minor code cleanup.
Add ability to updatePassword to angular.js.

* Add updatePassword to userService.js
* Add updatePassword function to userSettingsPanel.js
* Update userSettingsPanel.
Add UserMailer class.

I'm also adding an email for password_changed method.
Add PATCH action to update password on users_controller.
Display errorMessages in the template, if any.
Code cleanup.
Do custom checks for password and password_confirmation in users controller.

TODO: this needs to be moved to model layer.
Remove unecessary params from user_params.
Change devise password length validation to minimum of 6.
Fix how we display errors in the view.
Fix bug where function def was incorrect.
Add newlines to password_changed email.
Add more newlines to email!
Merge branch 'master' into email-on-password-change-29

Conflicts:
	app/controllers/users_controller.rb
Merge pull request #32 from vitaliyg/email-on-password-change-29

Email on password change 29