Now that that the merging GitHub Action is working, the docs need to be updated in regard to the geojson and topojson files. Also cleans up where this info is located, as it was in 'about' but should be in 'contributing'.
- add instructions for updating CSV and not JSON
- fix filepaths in merge_service_data.py
- add info about license agreement for contributors
- explain about large files that are currently missing
Fixes#7Fixes#15