Lint

Inside view: adding code to debug the hitch when flying on Mac OS. #369

	name: Lint
	on:
	push: { branches: [ "master" ] }
	pull_request: { branches: [ "master" ] }

	jobs:
	codespell:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Install dependencies
	shell: bash -l {0}
	run: \|
	sudo apt-get install -y codespell
	sudo apt-get install -y pycodestyle
	sudo pip install cython-lint
	- name: Run codespell
	shell: bash -l {0}
	run: codespell -L ans,arithmetics,inout,trough,compresser,rime,ba python
	- name: Run pycodestyle
	shell: bash -l {0}
	# We currently only check for some warnings. We should enable & fix more of them.
	run: \|
	pycodestyle --select=E111,E21,E221,E222,E225,E227,E228,E241,E251,E262,E265,E271,E272,E30,E401,E701,E702,E703,E704,E711,E713,E714,E721,W2,W3,W6 python/
	pycodestyle --filename=*.pyx --select=W2 cython/
	- name: Run cython-lint
	shell: bash -l {0}
	run: cython-lint --ignore=E501,E741 dev

	env:
	MAKEFLAGS: -j2

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