Remove CXX from cmake project languages
Remove tinytest submodule, and add files back
Fix several issues from clang's scan-build

  * src/qes_file.h: Small, very rare bugs created if realloc failed.
  * test/test.c: Fix broken CLI parsing bug.
  * test/test_seqfile.c: Fix possible double free on test failure.
Only enable stack-protector on UNIX-like systems

This adds the -fstack-protector flag to cc only if we're on UNIX.