Prepare for submissions

[ezwelty]

• [x] Rename temperature to measurement
• [x] Rename timestamp to profile
• [x] Both temperature and timestamp have a borehole_id. Either:
  • [x] Add composite foreign key temperature (timestamp_id, borehole_id) > timestamp (id, borehole_id)
• [x] Use natural primary key for temperature: (borehole_id, timestamp_id, depth)
• [x] Replace literal double quotes with single quotes
• [x] Remove redundant maxLength constraint from borehole.rgi_id
• [x] Add constraint to source.url (pattern: 'https?://.*')
• [x] Move id to first column of each table
• [x] Drop source.included, remove rows where 'False', and generate Markdown for GitHub
• [x] Convert coordinates to latitude, longitude, drop epsg
• [x] Move units out of field descriptions
• [x] Shorten and generalize tags:
  • published -> published (reported / imported)
  • from metadata -> submitted (reported / imported)
  • digitized from plot -> digitized
  • web map service approximation -> map approximation
  • web map service guess -> map guess
  • estimated from plot -> map approximation
  • plot digitizer -> digitized
  • manual -> published (reported)
  • import -> submitted (reported)
• [x] Rename quality columns
  • location_source
  • elevation_source
  • measurement_source
• [x] Tidy up borehole.notes: {column}: {note} | ...
• [x] Merge site_description into notes
• [x] Add timestamp.utc
• [x] Add borehole.label