CLI for `read_wv_xml.py` so matlab script can use

[7yl4r]

• [ ] + CLI to read_wv_xml.py & output metadata to .mat (is best?) file
• [ ] + ability to read .mat (?) metadata file
• [ ] modify submit_py.sh script
• [ ] cleanup deprecated matlab script for metadata parsing

[7yl4r]

The data we need for the Matlab code to run are:
NUMROWS
NUMCOLS
ABSCALFACTOR (there are 8 of these - one for each band)
FIRSTLINETIME (this contains the year, month, day, hour, minute, and second, which are each output to a different variable)
MEANSUNEL
MEANOFFNADIRVIEWANGLE
MEANSUNAZ
MEANSATAZ
MEANSATEL
CLOUDCOVER

Sooo whole new problem. The metadata format issue I'm having is caused by the fact that some of the images we received only contain 4 spectral bands instead of 8. These aren't usable anyway, so no need to revise the code to get them to work. When it encounters the line that corresponds to one of the other bands it just crashes, which is fine since we don't want them. No idea at this point how many images are 4 vs 8 bands... Hopefully not many.

[7yl4r]

Another feature that would be useful here: read the wv02 or wv03 from SATID attrib instead of reading from the filename.

[7yl4r]

Although commit 29919d1 doesn't address all of the issues listed here, it is good enough. If somebody still wants the matlab-specific features, just let me know.