Add a space homepage with the ability to both create new room and add existing rooms to the space. This uses a tree model for the space hierarchy and will go to any number of levels. The user should only see the add options if they have appropriate permissions.
This MR also combines the create space and room pages and adds a lot of optional functionality for managing space children.
Previously, some functions that conceptually belong to the connection needed to be in the Controller, since we didn't have a place to put them.
This fixes that by extending the Connection class in a similar way as we extend the Room class.
