Fix verbiage for registration closed/event ended

[cbaudouinjr]

Beginning with 2.0 we want to promote the concept of users being able to register at any point, however, the hackathon may not be currently accepting questionnaires. Doing this will allow volunteers to create accounts for check-in and other needed tools for the event. This removes the need for hackathons to create a "blanket" account for check-in.