- Create .vim folder too if missing
- Use filetype to categorize combo instead of file extension (this will
reset some combo counters, such as python: py.cmb -> python.cmb)
- Reload combo stats upon filetype change
- Check if combo tracking is already loaded on script start (to prevent
multiple instances when sourcing vimrc again)
- More verbose g:combo (access numbers directly at g:combo_counter and
g:best_combo)
To fix any lost combo score, rename the file accordingly in
~/.vim/.combo
