appveyor: support cmake & autotools using build matrix (like travis-ci has) This will allow us to avoid possible compilation regressions, and also some failures in different environments (for example because of different sizeof(size_t)). For example we can avoid next issues: - #361 - #314 - #311 (And I'm pretty sure that this is not complete list) And of course it reduce job for maintainers. But it also have one downside, appveyor doesn't have such concurrency like travis-ci, so it can take a while to finish the whole build, but we can resolve this later, or reduce build matrix to only one for autotools and one for cmake. Fixes: #364