Jump to 1.2.2.
Recover dev tag in development branch.
Improve the "spinning loading" feedback.

- Prevent users from navigating if there are pending ajax requests.

- Prevent the "loading" feedback from disappearing midway.
Jump to 1.2.3.
Remove communication error alert in favor of a console.error.
Jump to 1.2.4.
Merge branches 'develop' and 'master' of https://github.com/edelvalle/spine into develop

Conflicts:
	setup.py