Change grep colors to be alias

Environment variable was deprecated and was printing warnings

modules/environment/init.zsh

@@ -39,7 +39,7 @@ unsetopt CHECK_JOBS       # Don't report on jobs when shell exit.
 
 if zstyle -t ':prezto:environment:grep' color; then
   export GREP_COLOR='37;45'
-  export GREP_OPTIONS='--color=auto'
+  export GREP_OPTIONS=''
 fi
 
 #

runcoms/zshrc

@@ -21,3 +21,4 @@ alias open=xdg-open
 alias vi=vim
 alias subl=subl3
 alias tmux="TERM=xterm-256color tmux"
+alias grep="grep --color=auto"