Use /dev/random instead of /dev/urandom
/dev/random should be used for crypto-grade RNG.

To make sure use of /dev/random doesn't stall due to lack of entropy, install haveged which fills the entropy pool with sources such as network traffic, key strokes, etc.

On branch master
Your branch is up-to-date with 'origin/master'.

Changes to be committed:
	modified:   setup/dns.sh
	modified:   setup/system.sh
	modified:   setup/webmail.sh
use /dev/random for crypto-grade RNG with the help of haveged

Rather than pass `-r /dev/random` to ldns-keygen (it was `-r /dev/urandom`),
don't pass `-r` at all since /dev/random is the default.

Merges branch 'master' of github.com:pysiak/mailinabox