Add or verify the presence of the image scripts

We have existing scripts that should be added here. Some of them are listed below and some may already be there.

As a starting point, here are some tools we may want to get or build for visible light:

• PCA
• Histogram balancing
• Contrast enhancement
• [more] - see Parcak’s book
• Data storage and location
• NDVI
• GUI and non-GUI things (cf. Dan)