Enable compiling 64-bit on Windows using MSVC

Closes #5

.github/workflows/main.yml

@@ -25,3 +25,22 @@ jobs:
       - uses: actions/checkout@v2
       - name: Build for supported platforms on Ubuntu
         run: docker-compose run build-ubuntu
+  build-windows:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          submodules: recursive
+      - uses: ilammy/msvc-dev-cmd@v1
+      - name: Install SCons software construction tool
+        run: choco install python3 && python -m pip install scons
+      - name: Build for Windows 64-bit using MSVC
+        run: |
+          cd addons/godot_xterm/native/external/godot-cpp
+          scons platform=windows target=release bits=64 generate_bindings=yes
+          cd ../../
+          scons platform=windows target=release bits=64
+      - uses: actions/upload-artifact@v2
+        with:
+          name: bin
+          path: addons/godot_xterm/native/bin/*.dll