Merge pull request #8 from jahn96/drag_drop

Drag drop cells to Code Snippet Panel

Author: kpinnipa

package.json

@@ -48,9 +48,13 @@
  "@jupyterlab/docmanager": "^2.1.2",
  "@jupyterlab/docregistry": "^2.1.2",
  "@jupyterlab/fileeditor": "^2.1.2",
+ "@jupyterlab/nbformat": "^2.1.0",
  "@jupyterlab/notebook": "^2.1.2",
  "@jupyterlab/rendermime": "^2.1.1",
+ "@lumino/algorithm": "^1.3.2",
+ "@lumino/dragdrop": "^1.6.2",
  "@lumino/messaging": "^1.4.2",
+ "@lumino/properties": "^1.2.2",
  "@lumino/signaling": "^1.4.2",
  "@lumino/widgets": "^1.13.2",
  "@jupyterlab/services": "^5.0.0"