Resolved Issue #80.
The error that valgrind was referring to was the values of dy0, dy1, dy2, dy3. Setting these to an initial value of zero resolved the valgrind warnings and the SIGFPE errors.
Merge branch 'master' of ssh://github.com/campreilly/UnderSeaModelingLibrary
Removed debug code and corrected write_netcdf in data_grid.h.
Found many instances of debug code that were commented out, but not in ifdef statements. Should take a long pass over code to make sure there are no other instances of these commented out debug code.
write_netcdf function of data_grid was not functioning properly. NcDim was not working as intended for n-dimensional cases and NcVar varname needed to not have a temporary when being passed in.
Changed the derivative calculation in pchip to resolve issue #84.
Developed a workaround to get the old 4.2 netcdf_c++ interface working in Microsoft Visual C++ in Windows.  Instead of compiling netcdf_c++ separately, we've update the CMakeList.txt file to incorporate the NetCDF C++ classes directly into the USML libraries. It was the only way that we could figure out that supported all combinations of Release/Debug and Dynamic/Static libraries in Windows. Our intent is to eventually replace this with an interface to the new NetCDF-CXX4 interface.

These files are not used when compiling in Linux.  The Linux RPMs for netcdf include both the C and C++ interfaces.
Merge branch 'master' into windows_compile
Update installation documentation to reflect new Windows procedures.