added content selector
The selector is now opened in a modal dialog over the designer's dialog
The first modal dialog is hidden when another one is opened inside it.
Fixed the data service to use the server data attribute to obtain the app root
Removed the loading of the selector's scripts in the page editor
Code clean up
Implemented ability for the user of the content selector to specify template for selected items inside the directive's tag
Set the items per page to be 20
Merge branch 'ContentSelector'

Conflicts:
	Telerik.Sitefinity.Frontend/Designers/DesignerInitializer.cs
Selector code clean up
Merge branch 'master' into ContentSelector
Added selectors and services folders to the jsHint paths
Merge branch 'master' into ContentSelector
Added Pager
Fixed issues when two dialogs are opened several times
Fixed the isolated scope properties mapping of the selector
Implemented support for several selectors on a page
Fixed the transclusion of the closed dialog template so it can work with multiple dialogs
Added client unit tests for genericDataService
Fixed the error handling in the content selector