Add docs for autochop

Readme.rst

@@ -1933,6 +1933,29 @@ another savegame you can use the command list_export:
      autobutcher.bat
 
 
+autochop
+---------
+Automatically manage tree cutting designation to keep available logs withing given
+quotas.
+
+Open the dashboard by running:
+::  
+
+     getplants autochop
+
+The plugin must be activated (with 'a') before it can be used. You can then set logging quotas
+and restrict designations to specific burrows (with 'Enter') if desired. The plugin's activity
+cycle runs once every in game day.
+
+If you add
+::
+
+      enable getplants
+      
+to your dfhack.init there will be a hotkey to open the dashboard from the chop designation
+menu.
+
+
 autolabor
 ---------
 Automatically manage dwarf labors.