MAINT: Try adding github action for CI (draft)

Author: bluss

.github/workflows/ci.yml

@@ -0,0 +1,38 @@
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+
+name: Continuous integration
+
+
+env:
+  CARGO_TERM_COLOR: always
+  HOST: x86_64-unknown-linux-gnu
+  FEATURES: "test docs"
+
+jobs:
+  ci:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        rust:
+          - stable
+          - beta
+          - nightly
+          - 1.42.0  # MSRV
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: ${{ matrix.rust }}
+          override: true
+          components: rustfmt, clippy
+      - name: Install openblas
+        run: sudo apt-get install libopenblas-dev gfortran
+      - run: ./scripts/all-tests.sh "$FEATURES" ${{ matrix.rust }}
+