Fixed some errors in new topotools.py:
write function wrote points in wrong order (should start at NW corner),
Z was flipped relative to Y, so plots upside down,
needed to fix read for topo_type==1 to flip Z,
added topo3writer.
Note that Z now has same dimensions as X,Y and indexed same as X,Y.
Y and Z are both flipped updown relative to what was used in 5.1.0 version.
Fixed bad regression data in tests/dtopo1 after checking the results agree with regression data at commit 3ff3c90.
changed depth to topo in topotools for clarity
changed bathy to topo for clarity
changed 'project' to 'interp' for clarity since it's really interpolation onto a grid not projection that is done for unstructured grids
Modified Topography class so that __init__ does not require path and read has several new arguments to allow specifying path, topo_type,  unstructured when calling the read method.
Fixed several bugs in Topography and perhaps fixed crop method, but not yet completely tested.  See RJL: comments for concerns
Fixed (?) Topography to set .X and .Y based on .x and .y if available.  Added test of cropping with plot.
Improved test_new_topotools.py by adding assertions and test of crop function
Merge pull request #90 from rjleveque/topotools_fix_xyz

Fixed some errors in new topotools.py
Some fixes to topotools.py, adjusted plotting so pcolor and imshow pixels are centered on x,y of topo, added test data and plotting of Kahului Harbor
Merge branch 'master' into topotools_fix_xyz

Some additional fixes added to topotools beyond PR#90 that was just merged.

* master:
fixed docstring in test_plot_kahului
Fixed Topography.read when argument is a URL, deprecated get_topo function and added improved version fetch_topo_url that is now used by read.  Added a unit test.
Fixed new unit test for fetch_topo_url to delete metadata file
Do not set .z attribute of Topograophy class unless its an unstructured grid
Moved and renamed tests/test_topotools.py (and data file).  Need to see if Travis works ok.
Changed tests to get Travis to work(?)...
Take out plot tests and add main program to run these outside of nose.
Print directory and files to try to debug kahului file not found.
Travis fails for fetch_topo_url example so remove 'test' from the name of this test
test travis for plotting by adding apt-get install python-matplotlib to .travis.yml