Feature/meson subproject

[fnadeau]

Changelog: Feature: Add support for meson subproject.
Docs: conan-io/docs#3655

Issue related to this PR #15886

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[franramirez688]

@fnadeau LGTM! 👍 Thank you for the PR, it's ready to be merged 👏

I just added a couple of commits changing some minor things in the test.

[franramirez688]

I think that it's failing because of the Meson version in the CI

UPDATED: Checking the official documentation https://mesonbuild.com/Build-options.html. It reads so:

.... For versions of meson before 1.1, this file was called meson_options.txt.

In summary, renamed meson.options to meson_options.txt