Disabled reordering of IP addresses, so that the main IP is always eth0 and not a virtual interface of it.

FS#1341 - ISPConfig 3.0.2.2 modifies /etc/network/interfaces file in wrong way, while adding addiional IPs 

- Updated debian installation instructions.

- The updater still asks for the port number, but with this update the default number that is shown is read from the vhost file as xaver suggested.

Fixed: FS#1220 - /var/vmail/(domain)/(user) directories and files not delete when mail_user is deleted via remote.

Implemented: FS#1252 - Add permission system based on user / password to app installer 

Fixed: FS#1229 - ISPConfig3 creates the desired e-mail domain twice (on master server AND on the selected Slave) 

BugFix: FS#1234 - CLIENTNAME value when in reseller account - fixed with suggestion from Ciaran Johnston (cj). I make initial test and this worked fine but, need check if this fix impact affect any another part of ispconfig.