[ENH]Added missing screenshots. Resized them for better display without increasing too much area occupied. Hide remaining icons that were not hidden in previous commits. ToDo: bundle in Tiki the 200px thumbnail of screenshots, while keeping the bigger more detailed screenhost elsewhere online.

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@51036 b456876b-0849-0410-b77d-98878d47e9d5