just changed to the test of the sign up page

Sign up testing page
No big change

it is replaced by the file "signup.php"
signup page

just sign up for a new account,it will get infomation from the $_GET
sign in script

if the account and the password is all ok,put the user information to
the $_SESSION
adding functions and fixed bugs(test passed)

1.fixed some spelling error
2.test passed
used for the database config

such as fields' names,table names and...