publish a c-lib best practices guide

Tracking the idea of publishing a best practices guide for Haskell projects that use or bundle/vendor C libraries.

* Two recommended approaches:
* Use system clibs
* Bundle the clib in a standalone cabal package, then depend on that. e.g.:
* https://hackage.haskell.org/package/lzma-clib
* https://hackage.haskell.org/package/libyaml-clib
* Write up the recommended approaches and discourage other kinds of vendoring.

Use the issue's two recommended approaches as the outline: system C libraries, or a standalone Cabal package such as lzma-clib or libyaml-clib. Research and document those approaches, explain why other vendoring methods are discouraged, and consider the guide complete when the recommendations are clear for Haskell projects that use or bundle C libraries.

Written by the indexing model from the issue text.