isSame fails if std::string has a different size

[jmachowinski]

Hey,
isSame fails if std::string changed size.
The fix seems to be to ignore the size check in case
of a container. If you agree, I'll prepare a patch.

[doudou]

isSame should (and does) return false if the type descriptions are different. The underlying implementation detail that in the case of C++ and in some conditions, it's fine to unmarshal data that was generated from a certain type into a different type is just this: a pocolog/C++ implementation detail that should definitely not pollute the underlying model.

The right fix is to make sure the types match. Which is what the ruby pocolog implementation does in case of containers - detect this condition. That is, that it's fine to unmarshal a certain type definition into a different one, and feed the marshalled data to the local C++ type for unmarshalling.