Good first issue: typos discovered by codespell

[cclauss]

$ codespell --ignore-words-list="pard" # See #86

./build_mac.sh:226: unecessary ==> unnecessary
./openroast/freshroastsr700_mock.py:25: transistion ==> transition
./openroast/freshroastsr700_mock.py:441: transistion ==> transition
./openroast/freshroastsr700_mock.py:508: higer ==> higher
./openroast/views/recipeeditorwindow.py:357: wit ==> with
./openroast/views/recipeeditorwindow.py:395: atleast ==> at least
./openroast/views/recipestab.py:72: unecessary ==> unnecessary
./openroast/views/roasttab.py:49: diabled ==> disabled
./openroast/views/roasttab.py:146: guage ==> gauge
./build_tools/Openroast 1.2 for Windows README.rtf:12: withthe ==> with the
./docs/wiki/users_installing_mac.md:10: withthe ==> with the
./docs/wiki/users_installing_windows.md:9: withthe ==> with the
./docs/wiki/developers_installing_and_running.md:58: relevent ==> relevant

[rehanhaider]

Can I tackle this please?