XMLPropertyMapEntry::mbImportOnly and XMLPropertySetMapper bForExport

Although a rather large change this does not change the property
mappings or import/export behavior yet, but prepares for further
changes that add mappings for generating correct ODF and consuming
both old and new namespace/element/attribute names.

This is a combination of 4 commits:

added bool bForExport parameter to XMLPropertySetMapper ctor

Set to true for export, false for import. If export true, an
XMLPropertyMapEntry with mbImportOnly==true is not added to the
mappings. This to be able to have more than one mappings for import
(for example a current extension namespace and the future namespace
proposed to the ODF-TC, or corrected typos in element or attribute
names), but map only to one entry on export, of course.

(cherry picked from commit ebc1b2fe50c7ed1002ed8431410b8e2ac6e795b9)

Conflicts:
	dbaccess/source/filter/xml/xmlHelper.cxx
	xmloff/source/chart/PropertyMaps.cxx
	xmloff/source/draw/sdpropls.cxx
	xmloff/source/style/PageMasterPropMapper.cxx
	xmloff/source/table/XMLTableImport.cxx

prepared XMLPropertyMapEntry with mbImportOnly flag

(cherry picked from commit 9dd7ee88bd9835ae2bae36093100fcd651fd3aeb)

Conflicts:
	dbaccess/source/filter/xml/xmlHelper.cxx
	xmloff/source/table/XMLTableExport.cxx
	xmloff/source/text/txtprmap.cxx

just beautify this a little

(cherry picked from commit 44b4973fbd0f190906f36321b31215d80b363d52)

reordered member variables for 4 byte alignment

(cherry picked from commit dd902b8e256867b5d5fed06b52995f14d969f67d)

Change-Id: I15b03870fd14f110833037b6c0ff934624d72de1
Reviewed-on: https://gerrit.libreoffice.org/7144
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Miklos Vajna <vmiklos@collabora.co.uk>