Support ModelMetaData.IsRequired
* Update DataAnnotationsModelValidatorProvider to use ModelMetadata.IsRequired
* Adding tests and updating existing ones that didn't work with IsRequired

Fixes #533
Changes to support DisplayColumn attribute. Updating the MvcSample as well to start using DisplayColumn attribute. Adding UnitTests for the same.
Updating build.sh based on KRuntime changes
Enable request to reach base controller class's action
Fix #378
Remove ActionResultHelper
Fix #597
Remove ComponentResultHelper
Fix #598
Fix a build break in k10