Removed SystemEmailService + config

This was never used and adds to the installation burden,
so I have decided to remove for now.
Merged services.base subpackaged into services
Fixed routing for "Set up LTI outcomes"
Fixed class cast when computing LTI outcomes
Toned down the recently-gaudified flash message
Added "select for launch" to show ass page
Fix to author view: outcome variables were missed
Fix issue #29 in graphicGapMatchInteraction