Django-bootstrap3

- Fix invalid HTML in help texts (thanks luksen)
- Added `mark_safe` to placeholder (thanks ppo)
- Fix DateWidget import for newer Django versions (thanks clokep)

- Support for local languages in `url_replace_param` on Python 2 (362, thanks aamalev)
- Correct checking Mapping instance (363, thanks aamalev)
- Fix Django 1.11 import bug (see 369)
- Add Django 1.11 and Python 3.6 to tests
- Fix sdist issue with .pyc files

- Rolled back subresource integrity (see 353)
- Documentation fix (thanks clokep)

- **BREAKING** For Django >= 1.10 Remove everything to do with setting HTML attributes `required` (337) and `disabled` (345)
- Add `id` parameter to bootstrap_button (214)
- Add `set_placeholder` to field and form renderers (339, thanks predatell)
- Default button type to `btn-default`
- Add `addon_before_class` and `addon_after_class` (295, thanks DanWright91 and others)
- Fix handling of error class (170)
- No size class for checkboxes (318, thanks cybojenix)
- Fix warnings during install (thanks mfcovington)
- Fix rare RunTimeError when working without database (346, thanks Mactory)
- Add subresource integrity to external components (thanks mfcovington and Alex131089)
- Several improvements to documentation, tests, and comments. Thanks all!

- Print help text and errors in their own block (329, thanks Matoking)
- Improved page urls in pagination (fixes 323)
- Changed setup.py to allow `setup.py test` run tests
- Removed link target from active page in pagination (fixes 328)
- Fixed example for bootstrap_label (fixed 332)
- Fixed tests to support Django 1.10 handling of required attribute, see 337 (needs fixing)
- Added tests for Django 1.10
- Bootstrap to 3.3.7

- Fixed bug with widget attrs consistency (onysos)