Add area information to fields and beds

[braughtg]

Update the sample data and creation script for the sample database to support areas on fields and beds .

• - Add ACRE Unit and fd2_area field in farm_fd2 module as per Locations: adding area information to land assets FarmData2#373
• - Add data to src/sampleDB/sampleData/areas.csv to specify the area of some fields and beds but not all.
  • at least a few fields should not specify area.
  • at least one field with beds should not specify area for any beds
  • at least one field with beds should not specify area for at least one bed
• - Update src/sampleDB/addAreas.js to add the area information to the land assets created.
  • Use farm.asset uniformly in this script, currently it uses farm.log in a few places.
  • Remove farmosUtil and usernameMap because they are unused.
• - Build new Sample Database release.