Added GHOP Student Logic. Note that on creation of a GHOPStudent a GAE Task is created to update the taskswith the new GHOPStudent reference. This is due to the fact that we allow users to claim task without being a registered Student. Reviewed by: Lennard de Rijk

[nosetests]
exclude=pymox
with-coverage=1
cover-package=soc
cover-erase=1
cover-html=1
cover-html-dir=coverageResults
#debug=nose.plugins.cover