Repair silly error due to an extra sort that is not needed and was mixing wrongly the information when the scanning variable was not in increasng order

Changes to integrate and straight routines to handle better the needs for Salsa, including the hexapod scan (where datp.z is a string array)

Issue 26: Added extra output file for Salsa, containing the values of all the PV parameters, i.e. 45 params per scan point

Issue 31: Some changes to the way or reading/calibrating D2B files depending on the mode, raw vs no raw

Modifications for Salsa: Added phi/chi scans, corrected detector height, use PV values in str_fit output even for a single count

Added Gauss models and changed common parameters to be always P1=scaling, P2=DW, P3=position (And P4=fraction/weight in the case of individual models)

Changes to pass all tests. Expected value for IN16B test changed slightly (0.07%) because of several changes in the reading routine. D2B calibration file renamed to d2b_unittest.cal to be sure of picking the right one. Removed plotting in IN10B prox, as not needed for the test.

Corrected error in formula for QENS_IL2 in interface. Added extra output for Salsa, taking care of the case where the xtra information is not available (Issue 25)

(On progress) Work on event_file handler, incorporating the reading of the channels in the current experiment in D22 and the possibility of giving a pattern, e.g. xxo, to select the desired triggers.