Add linux aarch64 wheel support (#54)

.github/workflows/build.yml

@@ -57,3 +57,50 @@ jobs:
       with:
         name: wheels
         path: ./wheelhouse
+
+  build_aarch64_wheels:
+    name: Build wheel on aarch64
+    runs-on: ubuntu-18.04
+    strategy:
+      matrix:
+       python_tag: [ "cp35-*", "cp36-*", "cp37-*", "cp38-*", "cp39-*"]
+    env:
+      CIBW_ARCHS_LINUX: aarch64
+      CIBW_BUILD: ${{matrix.python_tag}}
+      CIBW_BEFORE_ALL: "yum -y update && yum install -y blas-devel lapack-devel suitesparse-devel"
+      CIBW_TEST_REQUIRES: "pytest cvxopt"
+      CIBW_TEST_COMMAND: "pytest -s {project}/module/tests -k \"not codegen and not mkl\" "
+
+    steps:
+    - uses: actions/checkout@master
+      with:
+        submodules: 'recursive'
+
+    - uses: actions/setup-python@v1
+      name: Install Python 3.9
+      with:
+        python-version: "3.9"
+
+    - name: Install cibuildwheel
+      run: |
+        python -m pip install cibuildwheel==1.10.0
+
+    - uses: docker/setup-qemu-action@v1
+      name: Set up QEMU
+
+    - name: Build wheels
+      run: |
+         python -m cibuildwheel --output-dir wheelhouse
+    - name: Release to pypi
+      if: github.event_name == 'push' && startsWith(github.event.ref, 'refs/tags')
+      env:
+        TWINE_USERNAME: __token__
+        TWINE_PASSWORD: ${{ secrets.pypi_password }}
+      run: |
+        python -m pip install --upgrade twine
+        twine upload wheelhouse/*
+    - name: Upload artifacts to github
+      uses: actions/upload-artifact@v1
+      with:
+        name: wheels
+        path: ./wheelhouse