first pass at notebook illustrating sshallow water Riemann solution
fixed run_and_make_plot script
fixed various things in ShallowWaterRiemannProblem.ipynb and script to run code, added second example
added phase plane plots
Fixed some problems in  ShallowWaterRiemannProblem.ipynb and added double-rarefaction example.  Posted at gist 8994740
fixed axes for animation and removed need for run_and_make_plots.sh
improvements to notebooks/riemann/shallow including: fixed Riemann solver when efix=.true., changed qinit so h*u computed properly, changed code in notebook to plot integral curves and Hugoniot loci properly on each side of ql and qr
Cannot have html <div> in a Heading cell, only in markdown (nbconvert fails)
Merge pull request #30 from rjleveque/riemann_shallow_notebook

Riemann solvers for shallow water equations notebook