Don't allow nontext UDF choice values, and change all existing ones to text
Fixes #950
Rework API to hook into our existing views
Merge pull request #953 from ahinz/topic/api-upgrade

Rework API to hook into our existing views
Merge pull request #992 from maurizi/udfChoicesTextOnly

Don't allow nontext UDF choice values, and change all existing ones to text
Clean up imports
Rename clobber to mask
Move global constants before class definition
Add an endpoint for getting instance info for maps near a point
Merge pull request #996 from maurizi/topic/instanceListForPoint

Instance list for point
Include advanced search configuration in instance info API endpoint
Merge pull request #998 from maurizi/topic/advancedSearchApiInfo

Advanced search API info
Fix broken migration
Add more information to instance info endpoint

Most of what we want is similar to the "form_extras" tags that we use in
our templates so part of this commit refactors for edits to share code
directly with the API.

This also fixes an bug where a model without an instance but with unit
data would crash the template tags.
Merge pull request #999 from ahinz/topic/add-more-info-to-api

Add more information to instance info endpoint
Mask unauthorized fields in api including UDFs

fixes #987 on github
Merge pull request #1000 from steventlamb/topic/mask_unauth_udfs

Topic/mask unauth udfs
Serialize values for DateFields differently than for DateTimeFields
Change date styling so that a full mm/dd/yyyy can be seen.  Fixes #895
Show Date Planted and Date Removed fields on tree detail, fixes #961