Refactor non-standard types in datrie to C99 types

This make splint and other things happy
update libqes to v0.1.2
Fix misc formatting and limited scope bugs

- Fix line length formatting in axe.c
- Add -D_FORTIFY_SOURCE=2 to CFLAGS
- Check for null before free when freeing datrie Trie structs
Add readme section on semver
Make GitSemVer.cmake; fix & split out git tagging

Changes to be committed:
      modified:   CMakeLists.txt
      new file:   cmake_modules/GitSemVer.cmake