Change from default TM style

[maning]

Lets tweak our style to avoid confusion from the original HOT Tasking Manager. See: https://github.com/hotosm/osm-tasking-manager2/issues/840

@batpad

[maning]

Suggested changes:

• [ ] OSM Tasking Manager title to OSM Great LA Building Import
• [ ] Change colorscheme to purple/gold ala LALakers. 😄

cc/ @jschleuss @cityhubla @batpad

[maning]

Stale.