Replace telnet with ssh, and writable /etc.

Dropbear(https://matt.ucc.asn.au/dropbear/dropbear.html) with password and pubkey support and working scp.
I could find easy way of mapping root home directory so i also made /etc writable and changed values in passwd/shadow - root password is "secret". I'm also trying to compile passwd from shadow(http://pkg-shadow.alioth.debian.org/) to allow for easy password change. 

With writable /etc its probably pointless to mount ppp config like in network.sh so i merged it into it.