Doc: Moving Qt Quick docs for new doc structure

-moved documentation from
   doc/src/qtquick2
   doc/src/localstorage
   doc/src/particles
 to src/quick/doc/
-fixed qdocconf file
-fixed snippets, images, and other qdoc errors related to the new
 directories
-fixed links in the main Qt Quick page

Change-Id: Ie3408c2624f623c17de07e5635d5c7284d02b973
Reviewed-by: Alan Alpert <alan.alpert@nokia.com>