Added Employee, Job, Location and Shift DisplayTemplates.
* Added some missing files that got lost on previous commits.
Dropdown Support in Shift Views:
* Created HtmlExtensions Helper
* Added DropDownActionAttributes for Employees, Jobs and Locations
* Created EditorTemplates for Employees, Jobs and Locations
* Shift controller action methods use DropDownActionAttributes
* Shift Create view shows Employee, Job and Location
* Added migration for Shift start and stop time
* Editied Shift model to support start and stop times, and use dropdown templates for Employee, Job and Location