Add first features workflow

github/workflows/features.yml

@@ -0,0 +1,27 @@
+on:
+  push:
+    branches: [master]
+  pull_request:
+name: cargo hack
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+      - uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Install cargo-hack
+        uses: actions-rs/install@v0.1
+        with:
+          crate: cargo-hack
+          version: latest
+          use-tool-cache: true
+      - name: cargo hack
+        uses: actions-rs/cargo@v1
+        with:
+          command: hack
+          args: --feature-powerset --exclude-no-default-features check