Revert "ebfret.ui.*: changed hgetset -> handle"

This reverts commit 696e5716085c4ece3b39cc34fdbe3083c177486a.
ebfret.analysis.dist.dirichlet.h_step: use Newton solver

Replaced non-linear solver with faster and more reliable method
that uses Newton-Raphson
added ebfret.analysis.dist.normgamma.h_step

Newton-Raphson solver for empirical bayes updates.
ebfret.analysis.hmm.h_step: Use Newton Raphson

Updated to use new Newton-Raphson method for normal-gamma priors
ebfret.analysis.dist.dirichlet.h_step: minor fixes
ebfret.analysis.dist.normgamma.h_step: minor fixes
ebfret.analysis.dist.normwish.m_step: return expectation values
ebfret.analysis.hmm.m_step: return expectation values
ebfret.analysis.hmm.h_step: optionally iterate over updates

If expectation values are supplied the posterior is iteratively
recalculated from the updated prior. This allows faster convergence.
ebfret.analysis.hmm.vbayes: return expectation values
Various updates to UI

* We now track time since last redraw outside run_vbayes call
* We now update the hyperparameters at intervals 0.1 * N
* We now run a full iterative hyperparameter update at the end of
  each cycle
ebfret.analysis.dist.normgamma.h_step: fixed convergence check
ebfret.ui.MainWindow: reset analysis when photobleaching is removed

Priors need to be recalculated after noise at the end of the time
series is removed.
ebfret.ui.MainWindow.run_ebayes: Minor fixes

* Set gui run state to false after analysis completed
* Check convergence separately from max iterations
ebfret.ui.MainWindow: cosmetic edits