Preliminary support for controls, courses and classes

A lot of it is placeholder. The config.py file is becoming unwieldy. Perhaps nodes in the config file should refer to each other via IDs or names instead of having raw object references. Perhaps more of the config should be constructed programmatically?

There will be problems with swedish characters inside config.py too.
Improved course and class generation; handling of swedish characters

Courses are generated from OCAD file format. Classes are described in a JSON document. ÅÄÖ can be used in either file.

Classes can be either single-leg with no forks, or pair-relay (expected to have forks). Entry fees are not yet populated correctly in classes.