Convert install scripts to python

[AgentK9]

Python is more universal than perl and allows for better extensibility and portability, not to mention readability.

[mstorsjo]

I'm somewhat ambivalent about this PR. (I haven't studied your suggested code in detail yet.)

Yes, python is probably to prefer over perl for the fixinclude and lowercase scripts. But for the install.sh script, I'm not really sure about whether this is a net win or loss - what do we gain from converting that to python?

(The actions run that I just enabled will probably fail; this is due to a tool regression that I've worked around on master; if you rebase your branch on latest master, it should run successfully again.)

[AgentK9]

Hello,

Thanks so much for your time in reviewing this. I have merged main into my branch. If you'd like, I can also squash all of these commits.

Here are a few reasons why the install.sh script should be changed along with the others:

1. Unified Codebase: Aligns with the existing Python components, streamlining maintenance.
2. Inclusivity: Facilitates contributions from Windows developers unfamiliar with GNU shell/sh.
3. Versatility: Enhances portability and allows for future feature integrations with ease.

I'd really appreciate any feedback you have.

[SaifRushdHadad]

I'm somewhat ambivalent about this PR. (I haven't studied your suggested code in detail yet.)

@mstorsjo, I was wondering if you had reviewed the suggested changes? I know it has been some time since the PR was submitted but rebasing and updating should be doable.