#3 Enhanced NIST.pyd functionality

[James Webber]

NIST.pyd is barebones right now--it takes a spectrum (in a very specific format) and returns its score (and nothing else). One simple enhancement would be to add a few other functions, like a search that also returns the top-scoring peptide, or a search that takes a scan in a more intuitive format like [(mz0,intensity0), (mz1,intensity1) ... ]