Make sure pages are initialized on command Output
Fix QA

The undefined variable raised an error which made the QA process think 
that there is something wrong with the layout files.
Multi paragraph text fixed, padding on textformat

* Better multi paragraph/pagebreak support (split)
* padding-top and margin-top for text formats (...bottom will follow)
New func sd:variable-exists, changed sd:variable

New layout function sd:variable-exists to check of a variable is non-nil.
The semantics are not perfect, but at the moment this will do. To be changed
later on.

Also changed the semantics (backward compatible) of sd:variable() which
now accepts more than one argument that are concatenated.