Make AES-128 tests obligatory
Merge branch 'master' into binary-format
Add CryptographicAlgorithmSerializer

The object net.secloud.core.utils.CryptographicAlgorithmSerializer
allows to (de)serialize crypto algorithm settings.
Add readList and writeList to BinaryReaderWriter
Enrich Objects to contain descendants info

The net.secloud.core.Tree and net.secloud.core.Commit classes now
contain IDs and keys to access their descendant objects.