Loading of CDS into the CDS tab

CDS when loaded are now shown in the CDS tab.
Need to setup event so that the descriptor is adjusted inside the
analysis object when updated in the GUI.
Need to use the comments attribute within the floodestimation
descriptors attribute
Improved usage of single analysis object

Still lots to do with the linkage between the gui and the
floodestimation analysis object not complete, too much to list.
Probably full of bugs.