Fixed #15529 -- More permissive geojson syntax in constructor

Thanks Wouter Klein Heerenbrink for the report.
Fixed #18508 -- tests for repeated deletion bug in ModelFormSet

The ticket's issue was already fixed by patch for #14877.
Improved resource limits handling in the kqueue autoreloader.

Refs #21356. Thanks Loïc.
Fixed #21359 -- Corrected MySQL collation name in databases docs

Thanks k_sze for the report.
Fixed #21364 -- Specified InnoDB full-text support from MySQL 5.6.4 on

Thanks thevlad at gmail.com for the report.
Fixed #21302 -- Fixed unused imports and import *.