Minor cleanup

Author: Todd Leonhardt

cmd2.py

@@ -1554,7 +1554,7 @@ def onecmd_plus_hooks(cmd_plus_args):
             interp = InteractiveConsole(locals=localvars)
             interp.runcode('import sys, os;sys.path.insert(0, os.getcwd())')
 
-            if arg.strip():
+            if arg:
                 interp.runcode(arg)
             else:
                 # noinspection PyShadowingBuiltins