Validated blank space in username field

Validated a case where the user was able to insert blank space in
username field in the Register step

Signed-off-by: Carlos Oliveira <carlospecter@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Used browserid's default algorythm to create user

The default algorythm generates a hash to save in database

Signed-off-by: Carlos Oliveira <carlospecter@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>