build: introduce GitHub actions

Author: matejcik

.github/workflows/python-package.yml

@@ -0,0 +1,29 @@
+# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
+# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
+
+name: Python package
+
+on: [push, pull_request]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.5", "3.6", "3.7", "3.8", "3.9", "3.10-dev", "pypy-3.7"]
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v2
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install package
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install .
+    - name: Run test
+      run: |
+        python tests/test_mnemonic.py

.github/workflows/style-check.yml

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+name: Check style and dist build
+
+on: [push, pull_request]
+
+jobs:
+  check_style:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python
+      uses: actions/setup-python@v2
+      with:
+        python-version: '3.x'
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install --upgrade black flake8 wheel mypy
+    - name: Check style
+      run: make style_check
+    - name: Check dist
+      run: make dist