auto fill sorting colums in ActiveDataProvider if none are configured
Lazy fallback of label creation for Sort class
Refactor DataColum to use model label for sorting link
DataColumn: Allow setting label of sort link via short syntax

attribute:type:Header should also affect sort link
use `@inheritdoc` for ActiveDataProvider::setSort
Added SafeValidator.
minor fixes of debugger.
bug fix of form generator.
finished rule generation for model generator.
Fixes #790: added visible for Nav and Dropdown
Fixes #21: implemented jQueryUI Slider
Fixed typo and code style
More tests for ArrayHelper and Inflector
fixed typos in ArrayHelperBase phpdoc
Added note about theme asset bundle to bootstrap widgets guide
more tests for FileHelper
Finished model generator.
added label option to Sort::link()
css fix.
introduced DataColumn::label property