Add matlab-json submodule

Although it's not native, relying on a robust java library is a much
better solution than jsonlab. I'll slowly deprecate jsonlab.

--CAR
Big clean-up of a couple uwsource drivers

All those

gpib_string = blah;
gpib_string = sprintf(gpib_string, value);
obj.write(gpib_string)

lines drove me bonkers.
Update ExpScripter example with automatic measurment loading

--CAR
Update to matlab-json
Bug-fix: printing islogical instead of checking for logical
Pass instrument settings to InstrumentFactory

If we already have them then we don't need to reload just to get the
deviceName.

--CAR