Added a few image data types for RGPS.
Implemented measures2netcdf tool to convert gridded RGPS MEaSUREs products into netCDF files.
Minor changes for issues that Ed found with the products.
Minor changes to make sure that our netCDF file are CF compliant. Otherwise, they did not work with ncdump, panoply and friends.
Merge pull request #63 from rudigens/master

Pull latest changes
Merge pull request #67 from rudigens/master

Pull latest changes
Temporary check in.
Crossing dateline function.
New asf_subset tool. Preliminary check in.
Sorted through the dateline issues in generating the subset. About ready to go.
Forgot to update some build information.
Needed to sort through some Poly definition issue.
Had to change the sequence for a successful build with make.
Needed to make a few changes to the metadata for subsetting SMAP data. Excluded the lat/lon layers from being clipped to the polygon, since I need those layers complete to ensure that the geocoding is actually working.
Major overhaul of convert2vector functionality.
Forgot the vector functions.
Forgot the help functions as well.
Final part of refactoring the convert2vector code.
Forgot some build details.
Few minor changes to get Radarsat2 data to work. More clean up.