new mod inputs. metainfo uses name. others..

bets.php now has more text boxes when creating a matchup. description
and images are currently optional. event name mandatory. needs style.

signing in returns you to the previous page. registering and logging out
redirects to betmain.php.

changed user_meta column `uid` to use username instead of user id for
convenience. signuppage, signinpage, betmain and noteventhubs and
metainfo function also changed to reflect this.