update db-diagrams
Merge branch 'master' of github.com:andrea-bottoli/DSD
merge merge merge merge merge merge..:P
Merge branch 'master' of github.com:andrea-bottoli/DSD
Sorry, I don't know, what commits will be merged
Design_Description my last changes and changed SequenceDiagrams <- need to discuss
Merge branch 'master' of github.com:andrea-bottoli/DSD
another merge...:)