[1.5.x] Fixed #20204 - Consistent usage of url() in URL dispatcher documentation

Thanks Baptiste Mispelon for the patch and dave.lampton@ for the suggestion.

Backport of c852d45681 from master.
[1.5.x] Fixed #20237 -- Reenabled assertContains with binary parameter

Thanks Baptiste Mispelon for the review.
Backport of fe01404bb9 from master.
[1.5.x] Removed incorrect phrase from DecimalField docs

Backport of 408da7b457 from master
[1.5.x] Fixed #20243 - Clarified when RelatedManager.remove() exists.

Backport of 712a792713 from master
[1.5.x] Documented BoundField.label_tag

Backport of 0f99246b6 from master.
[1.5.x] Fixed #20211: Document backwards-incompatible change in BoundField.label_tag

Also cleaned up label escaping and consolidated the test suite regarding
label_tag.
Backport of ab686022f from master.
[1.5.x] Fixed #20248 - Clarified manage.py vs. django-admin.py

Backport of 8fc68af9c0 from master
[1.5.x] Fixed #20237 (again) Allowed binary parameter to assertContains

Backport of b04fd579d5 from master.
[1.5.x] Fixed #20252 -- Mentionned geojson Spatialite support from 1.5

Thanks burton449geo at gmail.com for the report.
Backport of d58e985aa from master.
[1.5.x] Fixed #20247 - Added some missing paths in the tutorial.

Thanks gsavix for the suggestion and patch.

Backport of aad5661c6c from master.
[1.5.x] Fixed geojson detection with Spatialite

This is a partial backport of commit eb9430fc4be1. Without this,
geojson support is never detected with Spatialite.
Refs #20252 and #19028.
[1.5.x] Fixed #20263 -- Corrected wording in the formset documentation.

Thanks to feraudyh at yahoo.com for the report.

Backport of 1de63cccb1 from master.
[1.5.x] Fixed #20262 -- Replaced a reference to the wrong model in the CBV doc.

Thanks to mossplix for the review and bmispelon for the review.

Backport of b0bbccf from master.
[1.5.x] Fixed #20266 -- Updated view example in CBV introduction

Thanks jim at hellolocals.com for the report.
Backport of 58b3a974fc from master.
[1.5.x] Fixed #20286 - Typo in static files docs.

Thanks bmispelon.

Backport of f71fdf83a8 from master
[1.5.x] Fixed #20285 - Added missing commas in translation docs.

Thanks cody.j.b.scott@

Backport of 9f7b277d2e from master
[1.5.x] Fixed #20270 -- Fixed error in AjaxResponseMixin documentation

Backport of 73c26f0c95 from master.
[1.5.x] Fixed #20307 -- Word repeated in tutorial.

Replaced "the the" in the tutorial with "the".

Backport of f17aa99 from master.
[1.5.x] Fixed the reusable apps docs to use a rst file extension for the README and follow PEP8 a bit more.

Backport of 949b4e94588e73067f64b5b6d22e569a105baaf7 from master.
[1.5.x] Fixed a rST bug in the README template in the reusable apps docs.

Backport of db394e6ab2c1d3d53b8b8d691e995d0c3584b944 from master.