Item11267: Create FoswikOrgPlugin

This will initially implement the webhook to accept push
information from github for posting into foswiki tasks.

git-svn-id: http://svn.foswiki.org/trunk@17694 0b4bb1d4-4e5a-0410-9cc4-b2b747904278
Item11267: Add FoswikiOrgPlugin to the trunk pseudo-install

git-svn-id: http://svn.foswiki.org/trunk@17695 0b4bb1d4-4e5a-0410-9cc4-b2b747904278