Add github-ci release workflow

.github/workflows/release.yml

@@ -0,0 +1,31 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  release:
+    name: Release
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: Bootstrap
+      run: ./bootstrap.sh
+
+    - name: Configure
+      run: ./configure
+
+    - name: Make dist
+      run: make dist
+
+    - name: Upload dist to Release
+      uses: svenstaro/upload-release-action@v2
+      with:
+        repo_token: ${{ secrets.GITHUB_TOKEN }}
+        file: obstack-*.tar.gz
+        tag: ${{ github.ref }}
+        file_glob: true