1. Added scale to fit and scale to fill fitting modes.
2. Added APIs for a print app to specify which constraints imposed
by the print attributes were satsified during a layout so they
are not handled by the printer again, e.g. if the content is to
be in landscape the the app generated such content the printer
should rotate the content again.
3. Added some printer statuses.
4. Added a helper class that generates PDF documents with correct
size based on the passed in print attributes.
5. Exposed a ctor for PageRange which was hidden by mistake and apps
could not create page ranges. Added API for changing the printer
status.
Change-Id: If1334a61d2d931027b98075f653018d456b1b768