QuickBayes algorithm improvements

[robertapplin]

Description
There are a couple of improvements we need to make to the BayesQuasi2 and BayesStretch2 algorithms which use the quickBayes package, so that they have similar features to the BayesQuasi and BayesStretch algorithms.

• linear = sloping for v2 algorithms
• Sequential Fit option in Stretch is not possible. Its no longer a sequential fit by the sounds, because its done in parallel? Need to check
• Fixed width missing feature
• Maybe different name for output workspaces for quickbayes to make it easier to test
• One little bug - quickbayes uses Gamma instead of FWHM so plotting from gui doesn't work.

Other improvements before we can do a switch:

• The Stretch calculation needs to be faster

Acceptance criteria:

• The BayesQuasi2 and BayesStretch2 algorithms have the same features as BayesQuasi and BayesStretch
• The BayesStretch2 calculation completes within a reasonable time