Add snowballing functionality #184

	name: test-suite
	on: [push, pull_request]
	jobs:
	test-master:
	name: pytest
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	with:
	path: datatools

	- uses: actions/setup-python@v1
	with:
	python-version: '3.8' # Version range or exact version of a Python version to use, using semvers version range syntax.
	architecture: 'x64' # (x64 or x86)
	- name: Install packages and run tests
	run: \|
	pip install pytest
	pip install --upgrade setuptools>=41.0.0
	git clone https://github.com/asreview/asreview.git
	cd asreview
	pip install .
	cd ..
	pip install ./datatools
	pytest datatools/tests

	#test-older:
	#name: pytest
	#runs-on: ubuntu-latest
	#strategy:
	#matrix:
	#asr_versions: []
	#steps:
	#- uses: actions/checkout@v2
	#- uses: actions/setup-python@v1
	#with:
	#python-version: '3.6' # Version range or exact version of a Python version to use, using semvers version range syntax.
	#architecture: 'x64' # (x64 or x86)
	#- name: Install packages and run tests
	#run: \|
	#pip install pytest
	#pip install setuptools>=41.0.0
	#pip install asreview==${{ matrix.asr_versions }}
	#pip install .
	#pytest tests

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