[SQL optimizations] - many small optimizations

• Bookmarks have only users, not usergroups
• added caching to the settings table
• removed notice message lookups (we are not really using those)...

ensure no extra white spaces are added to the provisioning templates editor

Openstack uses username/password.

[API] - minor fixes

- fixed api index action still refering to old restsapi gem
- currently forced apipie to load DSL so we can reuse its DSL in our views

api v1 - Users controller and tests

- split api routes to separate routes file
- better detection of permission failure in model
- fix ApiConstraints
- catch bad routes in api and return json
- render home#index links from restapi
- fixed resource params recognition

api v1 - operatingsystems controller

api v1 - architectures controler and tests

cleanup after merge conflict with latest develop branch

api v1 - render errors with rabl

better detection of permission failure in model
fix ApiConstraints
catch bad routes in api and return json

api v1 - render home#index links from restapi