Upgrade to Ubuntu 16.04

Created by: LuisAlejandro

The new Ubuntu LTS is here and our base images are eager to receive updated software. There should be some heavy testing before making this change. A rapid thinking makes me think of some questions:

• Does it break the dependencies we install?
• Every package we use is included in this new release?
• Does Python 3.5 pose a threat to the operativeness of our 2.7-based software?
• Odoo runs well in it?

If anyone wants to post tests of this kind, feel free to comment below your experience. I will do some too.