[1.4.x] Updated link to jQuery Cookie plugin site

Backport of 81f454a322 from master
[1.5.x] Fixed #20492 - Removed a broken link in GIS docs.

Backport of fbab3209fc from master
[1.4.x] Fixed #20523 - Incorrect form field for FilePathField.

Thanks sane4ka.sh@ for the report.

Backport of 1fdc3d256d from master
[1.4.x] Fixed regroup example.

Chicago was missing.

Backport of e6ff238 from master.
[1.4.x] Fixed #20326 - Corrected form wizard get_form() example.

Thanks tris@ for the report.

Backport of 646a2216e9 from master