(chocolateyGH-571) Arg parsing error should be warning

Instead of logging a debug message, argument parsing errors should be
reported as warnings in case the argument doesn't actually evaluate
appropriately later.

src/chocolatey/infrastructure/commandline/Options.cs

@@ -824,7 +824,7 @@ protected virtual bool Parse (string argument, OptionContext c)
 		    }
 		    catch (Exception ex)
 		    {
-                "chocolatey".Log().Debug("Parsing {0} resulted in exception:{1} {2}".format_with(argument,Environment.NewLine,ex.Message));
+                "chocolatey".Log().Warn("Parsing {0} resulted in exception:{1} {2}".format_with(argument, Environment.NewLine, ex.Message));
 		    }
 
 			return false;