Allow validators on sqla inline relations

* Added an ItemsRequired validator
* Make inline relation check form_args
* Don't apply Optional validator if Required validator was specified
* Test case: many emails for each user, but each user must have
  at least one email
Merge pull request #697 from pawl/master

Fix Time/DateTime Equals Filters For SQLAlchemy+SQLite
Merge pull request #695 from singingwolfboy/sqla-respect-required-validator-on-relations

sqla: respect required validator on relations
Upgrade jQuery to 2.1.1
Upgrade select2 to 3.5.2
Merge pull request #699 from singingwolfboy/jquery-2.1.1

Upgrade jQuery to 2.1.1
Merge pull request #700 from singingwolfboy/select2-3.5.2

Upgrade select2 to 3.5.2
Upgrade moment.js to 2.8.4
Merge pull request #701 from singingwolfboy/moment-2.8.4

Upgrade moment.js to 2.8.4
Merge remote-tracking branch 'upstream/master' into daterangefilter