CGLM uses anonymous structs, which is a C11 feature. When trying to
build the tests in C99 mode, you get warnings to that effect. Switching
to C11 fixes this.
* tests: new built-in test runner
* tests: update tests for new builtin test api
* tests: print test suite logs
* tests: remove cmocka from build files
* tests: colorize test suite log and remove redundant prints
Lowercased Makefiles don't get picked up by the .gitignore for example,
which always looks odd after configuring. This commit just puts a
capital 'M' in front, like it's common.