Add workflow

.github/workflows/main.yml

@@ -0,0 +1,48 @@
+# Based on https://github.com/galaxy119/EXILED/blob/master/.github/workflows/main.yml
+
+name: Build
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: windows-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Setup Nuget
+      uses: warrenbuckley/Setup-Nuget@v1
+
+    - name: Restore Packages
+      run: nuget restore Images.sln
+
+    - name: Setup MSBuild
+      uses: warrenbuckley/Setup-MSBuild@v1
+
+    - name: Download references
+      uses: carlosperate/download-file-action@v1.0.3
+      with:
+        file-url: 'https://www.exiled.host/build_deps/References.zip'
+        file-name: 'References.zip'
+
+    - name: Download 7zip
+      uses: carlosperate/download-file-action@v1.0.3
+      with:
+        file-url: 'https://www.exiled.host/7za.exe'
+        file-name: '7zip.exe'
+
+    - name: Extract Refs
+      run: ./7zip.exe e References.zip -oImages/lib/ -r -y
+
+    - name: Build
+      run: msbuild Images.sln -p:Configuration=release
+
+    - name: Upload Build
+      uses: actions/upload-artifact@v2
+      with:
+        name: Plugin DLL
+        path: Images/bin/Release/Images*.dll