#4 Small fix to enable correct derefferencing of references

[Arrndt Faulhaber]

According to Hessian protocol specs, not only Lists can be referenced but also Maps, the latest version (1.3.2) skips the reference tracking of maps, thus the dereferencing of objects often fails with an IndexOutOfBounds-Exception

Here is a very small patch which fixes this behavior (at least for the deserialization - didn't yet look at the serialization side...).

Cheers, Arndt

[Arrndt Faulhaber]

Patch against source of version 1.3.2 fixing references (deserialization side)