changes to the dependencies and stamp system: * dependencies can only be of type ValueNode * exactType is a boolean flag, not a separate RiResolvedType * use different Stamp subclasses for IntegerStamp, FloatStamp, ObjectStamp and GenericStamp * use different stamp for nodes that can be a target for dependencies * use different PhiNode constructors for value- and non-value-Phis * use correct stamps for ExceptionObjectNode and CurrentThread