RFS: openfoam-6.20180805

[Kurt Kremitzki <kkremitzki@gmail.com>]

Hello all,

I've been working on packaging OpenFOAM 5/6 for a bit now, and in fact
it's taken so long that the first patch release has occurred right as
I've finished.

I've made pull requests here:
https://salsa.debian.org/science-team/openfoam/merge_requests

My main motivation for packaging this comes from its use in FreeCAD's
CFD Workbench, not as an experienced user (yet), so review by anyone
already familiar with OpenFOAM would be greatly appreciated.

Thanks!