#12778, patch 01/17: fix a series of warnings from clang

git-svn-id: file:///svn/Scribus/trunk/Scribus@19590 11d20701-8431-0410-a711-e3c959e3b870
#12778, patch 02/17: fix a series of warnings from clang

git-svn-id: file:///svn/Scribus/trunk/Scribus@19591 11d20701-8431-0410-a711-e3c959e3b870
#12778, patch 03/17: fix a series of warnings from clang

git-svn-id: file:///svn/Scribus/trunk/Scribus@19592 11d20701-8431-0410-a711-e3c959e3b870
#12778, patch 04/17: fix a series of warnings from clang

git-svn-id: file:///svn/Scribus/trunk/Scribus@19593 11d20701-8431-0410-a711-e3c959e3b870
#12778, patch 5/17: fix a series of warnings from clang
This fix signature of SlaOutputDev::startPage(). The signature change was already present in poppler 0.24.x series.

git-svn-id: file:///svn/Scribus/trunk/Scribus@19595 11d20701-8431-0410-a711-e3c959e3b870
#12778, patch 06/17: fix a series of warnings from clang

git-svn-id: file:///svn/Scribus/trunk/Scribus@19596 11d20701-8431-0410-a711-e3c959e3b870