Update Glossary docbooks

proofread + update
update links + remove dead links
replace kickoff
add more info about breeze
use plasma instead of plasma/workspace etc
remove extender, strigi, apsfilter, easysoftware, magicfilter
remove google gadgets + superkaramba
remove dead + obsolete links for ghns, could not find any replacement
add info about different meaning of widgets in plasma from usebase plasma faq
REVIEW:128705