Patch syntax highlighting bug

I personally use ksh-style arrays, but I noticed that this plugin doesn't work when that setting is enabled. Adding this one line of code allows this plugin to work for users who include "setopt ksharrays" in their .zshrc file.

zsh-syntax-highlighting.zsh

@@ -85,6 +85,8 @@ _zsh_highlight()
 
   # Before we 'emulate -L', save the user's options
   local -A zsyh_user_options
+  # Retain 1-indexing of zsh arrays
+  setopt localoptions noksharrays
   if zmodload -e zsh/parameter; then
     zsyh_user_options=("${(@kv)options}")
   else