Add predis and custom lib for token management
Hide information about passwords if there was an error
Use redis storage for tokens

Tokens are now a SHA1 hash of the real SSP token and current
user email. They are stored on a redis server.

Verification URLs don't have the token visibile neither
email parameter anymore.
Remove tokens after using them
Use new token system when requesting a new password
Generate random tokens and stop using SSP Token lib
Remember and use a 'goto' URL when registering

The 'goto' parameter passed to newUser.php will be stored in redis
for that given user.

After a successful registration, a 'Log in' button will
be presented, which will ask the user to log in and
after authenticating will be redirected to the desired URL.