change SCRATCH to scratch
Modified fgmax_tools to add new class for both input and output
Fixed bug in Topography.read_header where N is used instead of N-1 to compute extent
changed class name from fgmax to FGmaxGrid
moved discrete colormap functions from fgmax_tools to geoplot
changed FGmaxGrid attribute arr_time to arrival_time
fix masking of fgmax outputs, remove zeta and inundated from fgmax since these depend on sea_level and better for user to define what they need
change x,y attributes of FGmaxGrid to X,Y since they are usually 2d arrays
Merge pull request #107 from rjleveque/dtopotools2

WIP: improving fgmax_tools