When "AvoidRecentDocs" is set to true, the loaded document is not added to the
recent documents list, avoiding the (a bit expensive) thumbnail creation.

Useful when loadComponentFromURL() is called from macros, or when LibreOffice
is controlled via UNO.  See the bug for an example.

Conflicts:
	sfx2/source/doc/objxtor.cxx

Change-Id: I99d516cae8b278199a01276686465f716b9b4cec