Map and Legend components rewritten using hooks.
Also, each category can now have multiple available colour scales.
These can be switched using a select dropdown in the legend.
* Add subtle border for age layer buildings
* Simplify map data queries
* Fix typo in updated construction layer query
* Enable data tile caching switch for development
* Enable turning tile cache off
* Use render time variables for highlight tiles
* Create building numbers map layer
* Create database view for simpler map queries
* Decrease min zoom for numbers layer
* Add building outlines to all map layers
* Adjust building numbers style and zoom level
* Revert "Create database view for simpler map queries"
This reverts commit e3c342cb7393f491c838df5654c2316a9dab08e1
which cannot be implemented before upgrading Postgres to min v11
