Class name verification, Show information in nodes

[NicoBa]

• verification of class names (no randomized class names necessary anymore)
• nodes show information (class names, filter operations...)
• datasink modal added
• wordcount example updated

[MonsJovis]

könntest du den merge conflict noch lösen?

[MonsJovis]

@NicoBa sry, musst leider nochmal manuell ran