--registerUser and scheduleConference now throw exceptions for null or
empty parameters
--scheduleConference now also adds the conference to the progChair's set
of conferences
added missing static field comment
--added try/catch to user registration action to catch exception for
null or empty parameters
--code improvements
--working commit (testing incomplete)
Merge branch 'master' of https://github.com/TCSS360Group5/MSEE.git