Code Cleanup: Move all public API headers to include/

[CustardEddy]

Many public header files (mostly for extensions) are located alongside their code, e.g. exa.h is in exa/, rather than in include/.

This is nit-picky/borderline OCD stuff, but I believe that we should institute and maintain a policy of keeping the public APIs in a single location. Equally, anything that's in include/ that isn't part of the public API should be relocated.

It's a moderate amount of work (and potentially disruptive), so I wanted to get peoples' thoughts before I JFDI.

I can see both sides of this, but I believe that it's mostly moving-around complexity, rather than increasing it. (The build files in include/ gets more complex, while the individual extensions get slightly simpler.)

Either way, a consistent policy (public headers stay within extensions, or they all go into include/) is probably a good idea.

[metux]

Sure. Feel free to submit PRs.
Most of those changes (maybe even all) should be doable within the current ABI version.