Merge branch 'master' of github.com:cooperative-computing-lab/cctools

Resolve difference between Dinesh's find_worker_by_random() and mine

Conflicts:
	sand/src/Makefile
	work_queue/src/work_queue.c
Merge branch 'master' of github.com:cooperative-computing-lab/cctools
Overwrite Ben's merge

Conflicts:
	work_queue/src/work_queue.c
Merge branch 'master' of github.com:cooperative-computing-lab/cctools
Change find_worker_by_random() from O(n^2) to O(n)
Ignore deprecation warnings
Add usage string to visualizer
Use mkdtemp for workspace directory
Show rules in a table rather than a list.
Use centered boxes for the histograms.

This solves the problem of bytes read/written not showing up.
Also, bytes written/read work better with MB.
Compute optimal number of bins, fix corner cases.
Use subprocess module, allowing wait for gnuplot.
close link after all data has been sent.

(also, send extra newline to indicate the end of data)
Change find_worker_by_random() from O(n^2) to O(n)

Conflicts:
	work_queue/src/work_queue.c
Check for successful task completion before putting output files into the cache.
Merge branch 'master' of github.com:cooperative-computing-lab/cctools
Better category names in makeflow's manual
Remove comments from the top of work_queue_worker.c indicating things that have already been fixed
Automatic logscale/range for visualizer.

Also, cleans most tics from axis, and removes some borders.
Do not compile bindings without swig
Merge pull request #139 from btovar/visualizer-two-steps

Visualizer two steps