bugfix #217 - Reference to java object is not maintained by objc

History AReference to java object is not maintained by objc, when the java object is garbage collected #217
Fix PR fixed #217 #219

The problem is that ObjCObject keep reference of native object pointer (peer) to java object in map where java object is maintained in week reference vo. As result all java objects that is not referenced at Java side are subject for GC. And this is wrong.