Configure username and email parameter chk /w etc

1.Check both by convert to lowercase to prevent duplicate Username and
Email that will be add/edit to Db also to use in convenient way to enter
data with case-INsensitive but in Db keep as case-sensitive.
2.Check username that is have contain space? If it yes do not add it to
Db tell user to try again.
3.Add minimum character for Username and Password length (6 and 8 char).