[Etherpad] Add admin, home button, delete after delay and announcement plugin

pica-etherpad/Dockerfile

@@ -7,9 +7,9 @@ FROM base as downloader
 
 ARG ETHERPAD_VERSION_BUILD=1.8.4
 ARG ETHERPAD_PLUGINS="\
-  ep_align ep_author_hover ep_chatdate ep_colibris_full_width \
-  ep_comments_page ep_countable ep_delete_empty_pads ep_font_color \
-  ep_font_family ep_headings2 ep_markdown ep_pad_activity_nofication_in_title \
+  ep_adminpads2 ep_align ep_author_hover ep_back_button ep_chatdate ep_colibris_full_width \
+  ep_comments_page ep_countable ep_delete_after_delay ep_delete_empty_pads ep_font_color \
+  ep_font_family ep_headings2 ep_markdown ep_massage_all ep_pad_activity_nofication_in_title \
   ep_pads_stats ep_page_view ep_prompt_for_name ep_set_title_on_pad \
   ep_subscript_and_superscript ep_tables3 ep_user_font_size"