Additional parameters were required to better match the granularity
of the libisis testsx

Refs #2945. Add a parameter into the MARI, MAPS, MERLIN and LET files that tells the loader (currently only LoadRaw) to take detector positions from the RAW file not from the IDF. Swapped UpdateInstrumentFromRaw for UpdateInstrumentFromFile and will add ISIS NeXus support soon.

Lower-case first letter of instruments and scripts directories. All our installers did this anyway and this will mean less manipulation of the properties file is needed. Re #2753.

Incorporated the PSD bleed tests into the Inelastic GUI. Also cleanup up a few things around variables names in the script along with updating the parameter files to hold defaults for the bleed test. Re #1925