adds containsNode method to Graph
adds new util methods to ParameterList
implements toString() for undirected and directed Node
rewrites handling of weight to use unified operation for generation
cleanup of weights
complete re-write of updates & batches

re-write of:
- updates
- batch
- batch generators
removes al generics from updates and batches to account for current
changes of the graph data structures

minor change:
- dna.io.util.Keywords is removed and all entries moved to config files
adds graph generators from file / dir