Cherry-pick of 5717e6bd68c227c03e766ef09527b

First steps to have a proper admin area with its own menu
Cherry-pick of 34832ebf3aeb199afdadf892e

Adding chosen.js
Temporary moving the workers view link to the admin menu

I know it's not the correct place, but
the current location looks even worse to me
User management view in the admin area
Tests for the users management list
Merge pull request #58 from ancorgs/devel

Users management view