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
Sorting by modified date
Python3. See PEP 3113 for lambda arguments
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
Check if list of editable extension is empty. Edit action is not allowed if list is empty
add date/datetime/time range filters, add filter tests, combine jinja2 logic for active filters (from models/layout.html) with filters.js
Support callable base_path in FileUploadField
fix issue #369 by changing 'Model' to 'Record'
add basic tests for modelview localization, fix issue #692
add flask-babelex to travis configs
use as_unicode for bootstrap3 compatibility
Merge pull request #705 from Diaoul/base_path_callable

Support callable base_path in FileUploadField
Merge pull request #703 from pawl/daterange_filters

Add date/datetime/time range filters for SQLAlchemy, combine active/new filter generation logic
Merge pull request #706 from pawl/issue_369_2

fix issue #369 by changing 'Model' to 'Record'