Added symbol tests (#15)

.github/workflows/test.yaml

@@ -0,0 +1,15 @@
+name: Test
+on: [push, pull_request]
+
+jobs:
+  build:
+    name: NickelMenu / Symbols
+    runs-on: ubuntu-latest
+    container: docker.io/golang:1.14
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v1
+    - name: Build
+      run: cd test/syms && go build -o ../../test.syms .
+    - name: Run
+      run: cd src && ../test.syms