Support for organisations

[jussih]

Hämeenlinna is planning to use Varaamo with different organisations requiring per-organisation theming variables.

The UI should reflect colors and/or logos set by the current organisation. It is not yet known how the current organisation is selected.

Respa issue: CityOfHameenlinna/respa#2

[jussih]

Respa will have a new API endpoint for Organisations.

Varaamo will need to keep internal state of what is the current active organisation. Queries to the backend should filter Units/resources/etc with the active organisation. Colors used in the UI should be set using the color attributes of the Organisation.

In the topbar there should be a dropdown selector for the active organisation. This should probably be also selectable somehow via the URL the user arrives to the service.

[jussih]

An example how the 4 color attributes of an Organisation can map to the existing UI: