Fixed returned number of processors on Mac OSX. Tested on Mac OSX (and Ubuntu).
Source: http://stackoverflow.com/questions/150355/programmatically-find-the-number-of-cores-on-a-machine
Echo of random seedfile can be null.

The error message was created from the 'optargs' variable which is only correct if the -s whatever was the last item on the command line.
Use /dev/random by default if available.

General security principle,  always default to the most secure option. If someone wants to -s /dev/zero the still can of course,  but we assume they know what they are doing!

Not all non windows platforms have a /dev/random, you can disable it on Linux if you really want to, so we check first.
Downgraded RNG seed message to -v only

Now we read from /dev/random by default, this message isn't really that important anymore.
Merge remote-tracking branch 'goodluckart/bug/name-of-seedfile-in-error'
Merge remote-tracking branch 'goodluckart/feature/use-dev-random-by-default'
Merge remote-tracking branch 'bamse16/master'