Issue #27: change return code to exception in Main and Dotify (#47)

* Issue #27: change return code in Dotify to exception (also in Main)
	modified:   src/main/scala/modbat/mbt/Dotify.scala
	modified:   src/main/scala/modbat/mbt/Main.scala

* Line 45, I replaced return 1 by throw e in Main.scala

src/main/scala/modbat/mbt/Main.scala

@@ -42,7 +42,7 @@ object Main {
     } catch {
       case e: IllegalArgumentException => {
 	Log.error(e.getMessage())
-	return 1
+	throw e
       }
     }