Lots of smaller mobile fixes

* region can be deactivated in activeadmin
* smaller border around page content
* logo in top bar now with better spacing
* after signup is the map, not the profile
* sets the region in session when choosing one
Move all "Secrets" into secrets.yml (closes #445)
Merge pull request #453 from hacken-in/consolidate-secrets

Move all "Secrets" into secrets.yml (closes #445)
Merge pull request #451 from hacken-in/small-dropdown-fixes

Lots of smaller mobile fixes
Add venue controller
Adjust route to venues#show
Link to venue page
Add additional classes to venue address
Render url
render map for venue
Add description to venue
Show venue's events
Add german translation_key for venue