Replace makefile

[maedoc]

The basic makefile approach has become a headache due to different build configurations, compiler variations (and this, for a no-dep pure C99 lib). I don't expect this to get easier. Usually, this is divided into a configure & build step, like in CMake or autocont. CMake is great for cross-platform builds if your CMakeLists.txt is written correctly. Autoconf is not portable. Both require non-standard dependency to be installed.

Projects like MRtrix have gone with entirely custom Python based configure & build scripts, and this is worth looking at in this project.

Current configurations

• default dev mode, debug info, no optimization
• test coverage mode
• js
• "fast" for all optimizations, no debug

profiling instrumentation flags are set to one of

• generate profiling info
• use profiling info ("feedback directed optimization")
• gprof mode
• callgrind mode

Sanitizers These are only available starting with arbitrary versions of GCC/Clang of course.

• undefined behavior
• address

The address sanitizer does similar work to valgrind for invalid read/writes but seems to be much faster. Not sure if it catches all the same things, and it does not catch memory leaks (I think).

Targets / actions

• build the tests executable
• build the shared library object
• build benchmarks
• build docs / gh-pages from doxygen
• clean up all artifacts

[maedoc]

Let's suck it up and use CMake, I guess all this can be figured out.