Do not emit the structure of the dag to the log file; this duplicates
what is already in the dag file, and causes performance problems on very large dags.
Fixed duplicated action in Makefile: just install everything once.
Replace makeflow_log_parser with simpler makeflow_graph_log, to correspond to work_queue_graph_log.
Updated makeflow docs to reflect simplified log structure.
More doc cleanups to put the commonly needed features first.
Changed definition of directory dependency to correspond to the
design intent of makeflow and the implementation in Condor and Work Queue.
Added man page for makeflow_graph_log
Merge pull request #454 from dthain/makeflow-cleanup

Makeflow Log Cleanup