Remove wiki from repo and add link to esp3d.io

.github/workflows/wiki.yml

@@ -1,27 +0,0 @@
-name: Deploy Wiki
-
-on:
-  push:
-    paths:
-      # Trigger only when wiki directory changes
-      - 'wiki/**'
-    branches:
-      # And only on main branch
-      - 2.1.x
-
-jobs:
-  deploy-wiki:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-
-    - name: Push Wiki Changes
-      uses: Andrew-Chen-Wang/github-wiki-action@v3
-      env:
-        # Make sure you have that / at the end. We use rsync 
-        # WIKI_DIR's default is wiki/
-        WIKI_DIR: wiki/
-        GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        GH_MAIL: ${{ secrets.MY_EMAIL }}
-        GH_NAME: ${{ github.repository_owner }}
-        EXCLUDED_FILES: "a/ b.md"