Ported over more code from FSO

- Renamed VMInstruction.cs to VMThread.cs
- Created README.md
- Added Github CI

.github/workflows/build.yml

@@ -0,0 +1,23 @@
+name: build
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        dotnet: [ '3.1.200', '3.1.201' ]
+        build_mode: [ 'Release', 'Debug' ]
+        os: [ubuntu-latest, windows-latest, macOS-latest]
+    steps:
+    - uses: actions/checkout@v1
+    - name: Setup .NET Core
+      uses: actions/setup-dotnet@v1
+      with:
+          dotnet-version: ${{ matrix.dotnet }}
+    - name: Build
+      run: dotnet build src -c ${{ matrix.build_mode }}
+    - name: Run tests
+      run: dotnet test src -c ${{ matrix.build_mode }}