Upload a release asset on tag 🚀

Example:
```
git tag v1.45beta
git push origin v1.45beta
```

This creates a release, builds and pushes binary in `.tar.gz`

.github/workflows/upload-a-release-asset.yml

@@ -0,0 +1,48 @@
+name: Upload Release Asset
+
+on:
+  push:
+    tags:
+    - 'v*' # Push events to matching v*, i.e. v1.0, v20.15.10
+
+jobs:
+  build:
+    name: Upload Release Asset
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Get the version
+        id: get_version
+        run: echo ::set-output name=VERSION::${GITHUB_REF#refs/tags/}
+      - name: Update package list for i386
+        run: sudo dpkg --add-architecture i386 && sudo apt-get -y update
+      - name: Install packages
+        run: sudo apt-get -y install build-essential g++-multilib gcc-mingw-w64
+      - name: make
+        run: make
+      - name: make win32
+        run: make OSTYPE=win32
+      - name: Create asset
+        run: |
+          tar c addons | xz > jk_botti-${{ steps.get_version.outputs.VERSION  }}-release.tar.xz
+      - name: Create Release
+        id: create_release
+        uses: actions/create-release@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: ${{ github.ref }}
+          release_name: Release ${{ github.ref }}
+          draft: false
+          prerelease: false
+      - name: Upload Release Asset
+        id: upload-release-asset 
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_release.outputs.upload_url }} # This pulls from the CREATE RELEASE step above, referencing it's ID to get its outputs object, which include a `upload_url`. See this blog post for more info: https://jasonet.co/posts/new-features-of-github-actions/#passing-data-to-future-steps 
+          asset_path: ./jk_botti-${{ steps.get_version.outputs.VERSION  }}-release.tar.xz
+          asset_name: jk_botti-${{ steps.get_version.outputs.VERSION  }}-release.tar.xz
+          asset_content_type: application/zip