Resolves #40, Lowercased all user supplied usernames and email addresses in the account folder, and modified the regex in model.py to only accept lowercase characters.

Signed-off-by: Tyler O'Meara <Tyler@TylerOMeara.com>
Merge pull request #101 from Acidity/feature/issue40

Resolves #40, user provided usernames and email addresses are now case-insesitive.