ISIS-714: fixing manifest so that Isis custom mappings for DN picked up

... in addition (related):
* changing IsisBlobMapping to define its bytes as a java.io.Serializable column (maps to BLOB) rather than byte[] column (has no default mapping, so crashes and burns)
* update ToDoItem.java with additional JDO metadata to name the 3 inlined columns
ISIS-776: fixing incompatibility between Reflections usage and the mvn antrun:run / jettyconsole war

- Reflections does not expect to be given a .war file as a URL on the classpath, so instead rename to .jar.