save research progress ...
some cleaning in the code
Fixed log4j problem
No more "orphan" columns
Possible fix for blank node uri generation

Not extensively tested.
Clean up imports
Removed references to columnsCovered

Updated sesamemodelparser so it compiles, but no way to test it.
added JsonSerializer for Graph

Examples of use:
GraphUtil.exportJson(graph, filename);
graph = GraphUtil.importJson(filename);
Merge branch 'rdf_generation_blank_node_fix' into development
Merge branch 'no-orphans' into development
v192: no orphans + Jason's fixes to RDF generation
saved research progress ...
refreshing .gitignore
bug fix
add graphviz files (*.dot) to .gitignore
saved progress in integrating my research code into Karma ...
submitted initial version of automatic model suggestion!
saved progress on automatic model suggestion.
fixed some bugs of automatic model suggestion.
simple log mode change