ENH: Deprecate cmake for meson

[HaoZeke]

I like meson. Also beyond that, as shown in pypotlib meson subprojects make wrapper generation easier by:

• Separation of concerns (bindings in a separate repo)
• Less janky dependency handling (compared to git submodules)
• Generally being more readable / playing with environments better

The last one is subjective, but regardless, I think moving away from cmake would be a good step in modularity. Some considerations will probably come up in the migration related to the way meson handles sub-directories. @RuhiRG this could be a good starting point or a parallel task while you work on the bindings with existing installations :)

[RuhiRG]

Since I'm still getting used to build systems could we go over this together? Does the meson.build file used to generate the library I added during my pre-GSoC contribution not suffice?

[HaoZeke]

Since I'm still getting used to build systems could we go over this together?

Sure, will catch up on this in our update meeting.

[HaoZeke]

Does the meson.build file used to generate the library I added during my pre-GSoC contribution not suffice?

Deprecation is another thing to think about, but essentially we need to add one at the repo root to ensure that it can be used as a valid subproject in the bindings project.

[HaoZeke]

After discussion, it seems that the library builds fine, lua linkage is an issue, but that's not really part of GSoC.