[dev] Allow newlines in "Reason" in the course signup form
[dev] Added input placeholders for course creation form to specify format/range requirements
[dev] Added front-end validation of course signup form so that school year is filled in and in the correct integer range
[dev] Stopped csesoc.hs.head from being BCCd in signup confirmation emails
Merge pull request #21 from RafiB/dev

Fix bug where multilines in the reason in app form caused errors
Stop bcc'ing HS heads in emails to students/teachers after registration 
(thanks Rafi!)