docs: spelling fixes Squashed into 1 commit because I'm lazy: - non-existant -> nonexistent - accros -> across - comptatibility -> compatibility - requieres -> requires - aliast -> alias - unexistent -> nonexistent - convertion -> conversion - nto -> not

syntax: re
/figures/[^/]+\.png$
^html/
\.pyc$
~$
\.swp$
\.orig$
\.rej$
\.err$
^tests/easy_run.sh$
^build/
^MANIFEST$
^docs/tutorials/.*\.rst$
\.ico$
tests/\.testtimes