fixed bug in compare_gauges.py: depth plots were showing q[1,:] rather than q[0,:].  Changes benchmark comparison results.
fixed bug in compare_gauges.py: depth plots were showing q[1,:] rather than q[0,:].  Changes benchmark comparison results.

xinshengqin/tsunami_benchmarks,rjleveque/tsunami_benchmarks,xinshengqin/tsunami_benchmarks,rjleveque/tsunami_benchmarks