Documentation pass and changed error message for login()

Signed-off-by: Sebastian Lenartowicz <slenarto@uoguelph.ca>
Added register() function

Created a function that, given all the information about a new user, will add
it to the database.

Signed-off-by: Sebastian Lenartowicz <slenarto@uoguelph.ca>
Fixed regex in register()

Fixed the e-mail matching regex in the register() function so it will now
correctly match only valid e-mail addresses.

Signed-off-by: Sebastian Lenartowicz <slenarto@uoguelph.ca>
Merge branch 'master' of https://github.com/BlackBox3750/System