Add autoenv, automatic environment setup

Using a hook, automatically detect when `.enter` and `.exit` scripts
and source them when changing the shells current directory.

autoenv/autoenv.plugin.zsh

@@ -6,45 +6,14 @@
 # Global entered directories array.
 _autoenv_entered=()
 
-# Check if the given file is authorized, if not prompt the user to authorize,
-# ignore, or view the file. Authorized files and their modified times are
-# stored in the ~/.cache/autoenv/authorized file to make authorization
-# persistant.
-_autoenv_authorized() {
-  local file=$1
-  # If autoenv cache directory does not exist, create it.
-  local cache_dir=~/.config/autoenv
-  ! [ -d $cache_dir ] && mkdir -p $cache_dir
-  local authorized_file=$cache_dir/authorized
-  # Define the associative array to hold authorized key value pairs.
-  # If the authorized file exists, load it into an associative array.
-  typeset -A authorized=()
-  [ -f $authorized_file ] && typeset -A authorized=(`cat $authorized_file`)
-  # If the given file has been authorized, return.
-  local modified_time=`zstat +mtime $file`
-  [ "$authorized[$file]" = "$modified_time" ] && return
-  # Prompt to authorize file.
-  while true; do
-    read "answer?Authorize $file [Y/n/v]? "
-    case "$answer" in
-      y|Y|yes|'')             # Authorize the file.
-        authorized[$file]=$modified_time; break ;;
-      n|N|no) return 1 ;;     # Do not authorize the file.
-      v|V|view) cat $file ;;  # View the file.
-    esac
-  done
-  # Store authorized associative array in authorized file.
-  echo ${(kv)authorized) > $authorized_file
-}
-
 # Source an enter script and add its directory to the global entered
 # directories array.
 _autoenv_enter() {
   local entered=$1
-  # If entered exists in the entered directories array, return.
+  # If entered has already been sourced, return.
   (( ${+_autoenv_entered[${_autoenv_entered[(i)$entered]}]} )) && return
   # If the enter script is not authorized, return.
-  _autoenv_authorized $entered/.enter || return
+  # TODO: _autoenv_authorized $entered/.enter || return
   # Source the enter script.
   source $entered/.enter
   # Add the entered directory to the global entered array.
@@ -56,7 +25,7 @@ _autoenv_enter() {
 _autoenv_exit() {
   local entered=$1
   # If the exit script is not authorized, return.
-  _autoenv_authorized $entered/.exit || return
+  # TODO: _autoenv_authorized $entered/.exit || return
   # Source the exit script.
   source $entered/.exit
   # Remove the entered directory from the global entered array.
@@ -71,7 +40,7 @@ _autoenv_find_enter() {
   [ -f "$current/.enter" ] && echo $current
   # Loop until an enter script or the root directory is found.
   while true; do
-    # Go up one directory and make the path absolute.
+    # Walk up one directory and make the path absolute.
     local next=$current/..; local next=${next:A}
     # If the current directory equals the next directory, return.
     [[ $current == $next ]] && return || local current=$next