Tweak the command used for the "run" argument

- Using "start" will allow the batch script to return immediately,
  rather than waiting for the command to finish.
- Using "runemacs" (instead of plain "emacs") will hide the console
  window that is displayed while Emacs is running

bin/doom.cmd

@@ -5,10 +5,10 @@ PUSHD "%~dp0" >NUL
 
 IF "%1"=="run" (
    SHIFT
-   emacs -Q %* -l ..\init.el -f "doom|run-all-startup-hooks"
+   start runemacs -Q %* -l ..\init.el -f "doom|run-all-startup-hooks"
 ) ELSE (
    emacs --quick --script .\doom -- %*
 )
 
 POPD >NUL
-ECHO ON
+ECHO ON