Delete Sessions which cause deserialization errors

[marcust]

Warum ist das nicht so? Also in Hunter können wir Appserver gut damit auslasten nicht kompatible Sessions zu deserialisieren und ich denke nicht das das alles initial fails sind sonder auch ganz viele die bis zum nächsten Update der Session im Memcached die letzte Session versuchen zu deserialisieren.

Trying to deserialize sessions that are for some reason not
deserializable leads to continous retries at the moment.

As the data is apparently not loadable, it might be a better idea
to remove the data from memcached alltogether in order to avoid
expensive retries.

[magro]

For deserialization error this makes sense (you probably would also want to add the session id to the invalidSessionsCache), but not for other issues like a timeout. So this case should be handled more specifically and the session should not be deleted for all exceptions.
Having a test for this would be uber cool! :-)

[marcust]

Added the session Id to the invalidSessionCache and made the exception more specific.

Furthermode I added a simple test for the case of a desiralization error, a more complete integration test is out of scope at the moment.

[magro]

Looks good, nice test :-)

The TranscoderDeserializationException should also be thrown by other transcoders, but I can do this as well once I'm back from holidays.

[magro]

Thanx for the PR, I changed other transcoders to throw the TranscoderDeserializationException as well.