Added poster options widget to print dialog.

Note: This widget is unfunctional yet.
Some code cleanup.
Implemented poster options.
Small fix in poster.
Implemented alt. page rendering with GhostScript.
Improved performance for GhostScript rendering a lot.
Improved poster handling.
Small fixes.
Small code change in fileprinter class.
Set version number to 7.
Poster and scaling options are now in exclusion from each other.
Set version number to 8.
First page workaround for poster printing.

Processing only the first page of a multipage postscript document
in case of poster print. The utility poster is not able to process
multipage documents (yet).
Set print size A4 default in poster widget.
Media size description for poster widget.
Set version number to 9.
Added desktop file. User dialog for PostScript doc selection available.
User dialog for PostScript doc selection available.
Added KPrinter4 icons. Added more credits.
Updated de translations.