Update sign up fields to improve user experience

[brentguistwite]

• Disable minimum length on username(no real reason to have it)

• When signing up only ask for MINIMUM amount of info needed.(More fields = higher bounce rate).
  Ideally only require username and password.

• Change password length requirement. 10 characters is too long and an inconvenience for users.
  Consider only requiring only 5-7?

• When registering with all empty fields we provide no feedback. Crummy user experience.

• These changes will need to be reflected server side as well.