Initial commit of code supplied by David
First attempt to capture metadata in CIF framework.
Further improvement of normalisation and efficiency correction routines
Many changes to ease development and adjust to Echidna
Merge my workflow with official Gumtree workflow
Finished initial writing of efficiency input and correction application

There are still some bugs as seen by strange peaks in an efficiency-
corrected Vanadium data collection.
First draft of efficiency correction calculation and vertical offset
Finished calibration calculations and UI. Preliminary check of reduction

The calibration calculations now calculate vertical offset and efficiency
files.  These can be fed into the reduction routine and work correctly at
least for the Vanadium dataset used initially.