non-jira: fix display or velocity code in peekview when no-access message of a node is empty and not accessible

OO-2037: allow coaches and authors to upload and create tasks / solutions in the run view of the group task course element

OO-1867: upgrade selenium and arquillian libraries to support Firefox 46 and update the tests to work with them

OO-2031: revisions can be for individual and group, hold the user course environment only in the individual case