Words: Fix interop problem with LO/OO

Summary:
Words creates pagestyles with name "Standard" and displayname "Default".
Afaics the displayname is not used anywhere, so remove it.

There is a bug in LO/OO that creates a "Default" style where all words
style attributes go. The style is never used by LO/OO, effectivly
discarding all attributes.

Reviewers: boemann

Reviewed By: boemann

Subscribers: Calligra-Devel-list

Tags: #calligra:_3.0

Differential Revision: https://phabricator.kde.org/D16679