Use python3 for http-serve alias if available (#1193)

modules/utility/init.zsh

@@ -158,7 +158,11 @@ fi
 # Miscellaneous
 
 # Serves a directory via HTTP.
+if (( $+commands[python3] )); then
+  alias http-serve='python3 -m http.server'
+else
   alias http-serve='python -m SimpleHTTPServer'
+fi
 
 #
 # Functions