Platform specific qmakespec needs to enable: autogen_wmappmanifest and winphone. Manifest will be generated once and only for the application template.
The Manifest will generated from following variables:
* PRODUCTID - the GUID (application specific)
* PUBLISHERID - GUID (publisher specific)
* TARGET - short application name (executable)
* AUTHOR
* PUBLISHER
* DESCRIPTION - application description
Change-Id: I225c24dc256c57451775e37658080e88b842a7d8
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>