Add script for generating an amalgamated distribution

[athre0z]

This PR adds a script that creates an amalgamated build of Zydis. In other words: the script merges all sources files and internal headers into a single .c file and all public headers into a single .h files. The term "amalgamated" was inspired by libraries like SQLite that provide similar distributions.

I'll add a CI build (and perhaps automate attaching such a build to releases) in a separate PR. (amended to this PR)

Note: this PR is based on the remove-generateexportheader branch, because the export config was previously causing problems in the amalgamated builds. (merged and rebased on master)

[athre0z]

This name clashes with another STR_REGISTER somewhere in the generated formatter strings when doing amalgamated builds, so I had to rename it. I'll push a commit to also change that in gen_registers.py once this PR is merged.

[flobernd]

LGTM!

[athre0z]

Figured that it probably makes more sense to also add CI in this PR, so added a commit for that. Turned out that the CI's Python version isn't latest, so I had to downgrade a few things. Will clean up history after approval.

[Tachi107]

Turned out that the CI's Python version isn't latest, so I had to downgrade a few things.

In case you didn't know, GitHub's CI offers the possibility to run jobs in Docker images, so you're not limited to using Ubuntu LTS; if you need updated packages you could use Debian Testing, it's really nice :)

Here's a quick example (taken from Tachi107/cloudflare-ddns/.github/workflows/muon.yam):

jobs:
  muon:
    runs-on: ubuntu-latest
    container:
      image: debian:testing

    steps:
      ...build steps...

Edit: another advantage is that your build gets executed in a cleaner environment compared to the default one (as GitHub ships A LOT of software in their CI images), so the possibility of strange bugs related to the tests using unknown versions of installed library when they shouldn't is reduced

[athre0z]

That's good to know, thanks!