Moving all autoenv logic to the plugin file.

-Some of this was previously located in the directories lib.

-Also unsetting the cd override function created by autoenv and replacing
 it with a zsh hook.

lib/directories.zsh

@@ -30,9 +30,6 @@ cd () {
     cd ../../../..
   elif [[ "x$*" == "x......" ]]; then
     cd ../../../../..
-  elif [ -d ~/.autoenv ]; then
-    source ~/.autoenv/activate.sh
-    autoenv_cd "$@"
   else
     builtin cd "$@"
   fi

plugins/autoenv/autoenv.plugin.zsh

@@ -1,3 +1,11 @@
+# Add the functions from autoenv if it's installed.
+if [ -r ~/.autoenv/activate.sh ]; then
+    source ~/.autoenv/activate.sh
+    # Use a zsh hook instead of overriding the builtin cd.
+    unset -f cd
+    add-zsh-hook chpwd autoenv_init
+fi
+
 # The use_env call below is a reusable command to activate/create a new Python
 # virtualenv, requiring only a single declarative line of code in your .env files.
 # It only performs an action if the requested virtualenv is not the current one.