removed unused plugin from directory

docs/source/_data/plugins.yml

@@ -90,8 +90,6 @@
     - reaction
 - name: talk-plugin-rich-text
   description: Enables rich text plugins that save data as HTML.
-- name: talk-plugin-rich-text-pell
-  description: Enables the pell rich text editor.
 - name: talk-plugin-slack-notifications
   description: Sends all comments as notifications to a slack channel
 - name: talk-plugin-sort-most-liked
@@ -135,4 +133,4 @@
   description: Enables the dropdown used to display sorting options on the embed stream.
   tags:
     - default
-    - sorting
+    - sorting