added files to automatically enable server extension and nbextension

jupyter-config/jupyter_notebook_config.d/jupyter_openbis_extension.json

+{
+  "NotebookApp": {
+    "nbserver_extensions": {
+      "jupyter-openbis-extension.server": true,
+    }
+  }
+}

jupyter-config/nbconfig/notebook.d/jupyter_notebook_extension.json

+{
+  "load_extensions": {
+    "openbis/main": true
+  }
+}