update github action and logo

Author: cl117

.github/workflows/slate-action.yml

@@ -0,0 +1,11 @@
+on: push
+name: Create Slate Documentation on Push
+jobs:
+  slate-documentation:
+    runs-on: ubuntu-18.04
+    steps:
+    - uses: actions/checkout@master
+    - name: Build documentation
+      uses: docker://slatedocs/slate-action:2.0.0
+      env:
+        DOC_BASE_FOLDER = "."