Add checkbox, radiobutton, radiobuttongroup element interfaces
Merge remote-tracking branch 'upstream/master' into darcy-ui-i18-fundamental-ui-element-types

Conflicts:
	src/main/java/com/redhat/darcy/ui/Elements.java
Add Checkbox#check and Checkbox#uncheck
Merge branch 'master' into darcy-ui-i18-fundamental-ui-element-types
Rename RadioButton and RadioButtonGroup interfaces
Refactor RadioGroup interface
Revert RadioGroup interface
Remove RadioGroup interface for now
Or at least I thought it was removed
Add DateSelect and MultiSelect interfaces, update Elements static factories
Add fileSelect(s) to Elements factories
Fix code example
Merge FindsByChained into FindsByNested
For convenience, allow chaining locators in By.nested
Simplify AbstractViewElement usage
Fix ByNested and unit tests
Require parent element
Unwrap wrapped elements in ByNested
Merge pull request #33 from darcy-framework/wraps-element

Unwrap wrapped elements in ByNested
Return specific types in By factory methods

Let clients refer to them by their interface (as they should).