initial work on annotations
minor model changes
change delete protocol, fix tests
add migration tool script
ensure geojson parsing works
copy annotations on map_copied signal, refs #257
use geojson for annotations service
ignore scratch directory
annotations work - geojson fixes, validation, time

- remove id from properties, handle id at feature level as per
  the spec
- start work on form, migrate some parsing to there, error collecting
  in view
- accept ISO formatted times in CSV, use ISO formatting for output