Allow longer FTP username

Allow longer FTP username
change chars to 32

and made a maxlength="32" on ftp_management
Update zpanel_proftpd.sql
Update zpanel_proftpd.sql
Update zpanel_proftpd.sql
Update zpanel_proftpd.sql
Merge pull request #30 from Diablo925/master

FTP Username length now increased to 32 characters.