fdo#47677 - Track Changes Toolbar

Added new toolbar ("Changes") which contains accept, reject, comment,
protect, accept or reject, record and show within Writer.

Change-Id: Ic541f95f09b3897cdabd23a6e1070809f361cc16
(cherry picked from commit 686ab95e97e3a432fcccc88ae30b8ad6eed1b2b4)
Signed-off-by: Luboš Luňák <l.lunak@centrum.cz>
allow accepting/rejecting changes in a selection (bnc#874790)

More convenient than handling them one by one.