Qt assistant compat

Added new package "qt-assistant-compat" used to build software which use the help page in adp file format. 

"This package contains the Qt Assistant compatibility version, based  on Assistant Document Profile (.adp) files, and the associated  QtAssistantClient library, for compatibility with applications providing help in that format."

more info to > http://blog.qt.digia.com/blog/2010/06/22/qt-assistant-compat-version-available-as-extra-source-package/