Dsc 259

This request implements the extension of google metadata extractor to extract Tiff metadata during upload, and displays extracted metadata fields via the "View Tiff header metadata link" in the uploaded files page.
I wonder if the all the Drew Noakes code should go into a deeper package something like package banjo.meta.<drewsstuff> Not sure of the name but at least we could combine it into it's own package indicating that it's a cut and paste with a few edits.