update api
move Flags
[log] Add BitSetFlags.
[log] Move some files.
[log] Move PrintParameters.
[log] Move TimestampGetter.
[log] Add PermanentCommitsInfo.
[log] Move IntToIntMap and relative files to log.facade.utils package.
[log] Move PermanentGraph and relative files to log.facade.graph.permanent package.
[log] Add GraphWithHiddenNodes as PrintedGraph and GraphWithCommitInfo.
[log] Use BitSetFlags in PermanentGraphBuilder.