Add openfoam installation.

I doubt we'll use it given that they are very much recommending containers.
But calling a container from a container is a tad difficult!

scripts/openfoam.sh

@@ -0,0 +1,12 @@
+# NOTE: openfoam4 is NOT supported on the latest LTS release of Ubuntu.
+# See: https://openfoam.org/download/4-1-ubuntu/
+# Most notably, the releases supported are:
+#    14.04 LTS, codename trusty (32bit and 64bit)
+#    16.04 LTS, codename xenial (64bit only)
+#    16.10, codename yakkety (64bit only, added 4 Nov 2016)
+#    17.04, codename zesty (64bit only, added 16 Apr 2017)
+
+sudo sh -c "wget -O - https://dl.openfoam.org/gpg.key | apt-key add -"
+sudo add-apt-repository http://dl.openfoam.org/ubuntu
+sudo apt-get update
+sudo apt-get -y install openfoam4