fdo#82106 RTF import: fix missing tab after special footnote

Change-Id: I5ea45dbed652231acdcc3632ced728ed8bcb621a
Remove unused empty elements

Change-Id: I17815878be292bb23602232456648f9571b8de06
Sync oox -> writerfilter alias for wordprocessingml

The motivation is that once all the namespace aliases in
writerfilter/source/ooxml/model.xml match the ones in
oox/source/token/namespaces.txt, then the writerfilter copies could be
dropped.

Change-Id: I1f9abb8bb457189997f28c99b0f6b00660252c14