Add some more caching

* Cache room attribute values in Redis
* Memoize various functions during a single request context
Provide 5 instead of 3 stack frames in db log
Avoid warning about empty IN clause
Remove debug print
Improve import order in alembic script template
Fix wrongful rename
Use schemas for tables

* Core: indico
* Roombooking: roombooking
Properly handle schemas everywhere

- when deleting all tables
- when prepareing a new database
- when creating tables
Fix fix_sequences (include schema in setval call)
Show DB name in 'data will be erased' warning
Domain-based access control fixes
New logo!
Changed favicon
Dropdown menu: make selector configurable
Slightly nicer top bar/menu
Move _main to partials

Since it's needed basically everywhere
Icomoon icons for login/logout
Improved header, session bar and search box
Added dark yellow to palette
Improve questionable code in Serializer