Fixed #19665 -- Ensured proper stderr output for Command.run_from_argv

Thanks Stefan Koegl for the report and Simon Charette for the review.
Patch by Claude for #16084.
Added more shortcuts to i18n docs in index page.
Revert "Patch by Claude for #16084."

This reverts commit 2babab0bb351ff7a13fd23795f5e926a9bf95d22.
Moved has_changed logic from widget to form field

Refs #16612. Thanks Aymeric Augustin for the suggestion.
Fixed #18460 -- Fixed change detection of ReadOnlyPasswordHashField

Thanks jose.sanchez et ezeep.com for the report and Vladimir Ulupov
for the initial patch.
Used property decorators in django/forms.py
Fixed validation of email addresses when the local part contains an @.

See also BaseUserManager.normalize_email -- it uses rsplit.

Refs #4833.
Fixed #19540 -- Stopped using deprecated os.stat_float_times.
Fixed #19589 -- assertRegexpMatches is deprecated in Python 3.3.
Moved BooleanField 'required' validation in validate()
Fixed #17158 -- Used a non-ambiguous representation of SQL queries

when a correct representation cannot be obtained.
Fixed #18483 -- Marked hidden field error string for translation

Thanks Evil Clay for the report and Emil Stenstrom for the initial
patch.
Fixed #16123 -- Ensured strptime receive proper string type

strptime generates an UnicodeEncodeError when using a non-ascii
unicode string on Python 2.
Fixed two malformed links.
Fixed #19677 -- Introspection of recursive foreign keys under SQLite.

Thanks Simon Charette.
Fixed #19676 -- Supported 'self' foreign keys in inspectdb.

Thanks Georgy Kutsurua for the report and Simon Charette for the patch.
Added HTML5 email input type

Refs #16630.
Added HTML5 url input type

Refs #16630.
Fixed #19683 - Added a missing import in signing example.

Thanks sunsongxp@ for the report.