Update kwintabbox kcm docbook to plasma 5

Note:
The diff is completely misleading, because the latest docbook in kde 4 has <date>2014-03-10</date> + <releaseinfo>&kde; 4.11</releaseinfo>
but kwin master in kf5 has <date>2010-10-28</date> + <date>2015-07-24</date> <releaseinfo>&kde; 4.5</releaseinfo>
The diff against the latest kde4 docbook version 4.11 has only 4 or 5 lines
REVIEW:124475