REMP Plate Lookup Parser

New function to parse REMP plate lookup files.  Does some QC on the table:
 - Ensures that there are only two plate barcodes, removes extras, makes best guess on which one is a control

New UI features:
 - select compound from those in the REMP file.
 - Prev and Next compound buttons
 - select concentration by slider, shows actual conc beside slider, slider is in index units

Various other bug fixes and enhancements.