Merge pull request #20 from marqh/hfiles

Include all public headers in installation

Merge pull request #19 from marqh/cmake_fix

remove src double ref

Merge pull request #17 from rhattersley/cmake

Switch to CMake

Merge pull request #16 from rhattersley/storage-class

Fix storage class for message

Merge pull request #1 from pelson/update_from_svn

Pulled SVN version up from 5668 to 8231.

Import from PUMA.

A copy of the "libmo_unpack" directory from:
 https://puma.nerc.ac.uk/trac/UM_TOOLS/attachment/wiki/unpack/unpack-160114.tgz