Fixed #12579 -- Noted QuerySet.get_or_create() depends on database unique constraints.

Thanks timmolendijk, jdunck, vijay_shanker, and loic84.
Fixed #20673 -- Clarified that HttpRequest.user uses AUTH_USER_MODEL.

Thanks littlepig for the report.
Fixed #20134 -- Correct list of fields that UserManager requires.

Thanks semenov and pegler.
fixed grammar
Fixed #19940 -- Made test.runner.setup_databases properly handle aliases for default db.

Thanks simonpercivall.
Merge pull request #1331 from hekevintran/patch-1

fixed grammar
Fixed #19539 -- Updated custom model fields example for Python 3.

Thanks astorije@ for the report.
Fixed #20561 -- Emphasized that QuerySet.distinct([*fields]) is only supported by Postgres.

Thanks jtiai for the suggestion.
Fixed #20224 -- Update docs examples which mention __unicode__

Thanks Marc Tamlyn and Tim Graham for the review.
Deprecate usage of boolean value for widget attributes

Django 1.7 will loudly warn when widget attributes are assigned
boolean values. In Django 1.8, False will mean attribute is not
present while True will mean attribute present without value.
Refs #20684.
Tweaked proj string regex in gis tests
Added release dates for gis libs as doc comments
[gis] Dropped official support for GDAL < 1.6
Fixed #14006 -- Documented that Field's 'description' attribute is interpolated with field.__dict__

Thanks abeld for the suggestion.