Module-file format: Hash type at beginning, result at end?

[Reinier Zwitserloot]

By moving the hash itself to the top of the module file, a tool that creates
module files either needs to be 2-pass, or needs to store the entire content
to be written in memory. It seems a bit awkward, but storing the _type_ of
hash at the top and the _hash_ itself at the bottom is the most convenient
for both writers and readers. Same applies to per-section hashes.

--Roel Spilker and Reinier Zwitserloot