* Fix incorrect code indentation
* Remove unnecessary vendor prefix for `box-sizing` - all modern browsers now support this unprefixed
* Remove incorrect `<label>` and change static controls to readonly inputs
* Allow `<img>` elements without `src` to allow for `holder.js` images used in the docs, which lack `src` and use `data-src` instead
* fix form-inline with flex enabled
* grunt
* fix alignment of labels
* shorter if syntax
* add new form example to docs for now
* update inline form docs usage guidelines
* responsive margins
* better margin utils
* fix sizing of .form-check
* flexbox alignment of .form-check
* no need to change direction
* support custom controls in inline form, for default and flex modes
* add example of custom select and checks to docs
* remove hidden and visible label variants since we cover that in the usage guidelines at the start and include hidden labels everywhere
* use property value instead of layout name
* apply to all labels
* add a visible label, space it out
* add id
- Remove margin-bottom override in favor of .mb-0 utility class
- Apply the input line-height styles to match
- Remove the min-height to match the input
* descriptions for getting started pages
* descriptions for layout
* add content page descriptions
* more descriptions, updates to some existing ones
* correct site url
* add social stuff to config for twitter cards
* add twitter meta tags; use large image for homepage and regular card for all others
* add the assets
* more site config
* more social shiz to partial, remove existing meta for the partial, remove page title from homepage for simpler if statements
- Move disabled radio and checkbox styles to Reboot
- Collapse .radio and .checkbox into single class, .form-check
- Collapse .radio-inline and .checkbox-inline into single class, .form-check-inline
- Require classes for sub-elements in both new classes
- Give some guidance on when someone might use any of the three
validation states. Fixes#18702.
- Improve the examples to provide examples of supporting validation
text with the new `.form-control-feedback`, as well as always-present
help text. Nullifies #18704.
