Changed how I run OF cases

I didn't want to specify things over and over, so too I didn't want to
have to keep looking though really really log run files. Finally, it was
a waste to have up to 100 nodes spinning idle whilst 1 node is doing the
single threaded portion. So it's now all broken up into individual
scripts. These should be copied into your case folder - Typically I use
a base_case/modification structure so the positioning of files makes
sense. Also I'd symlink the runCase script to the _script folder because
... #engineering