ebfret.plot.spectrum: change default color range
ebfret.analysis.hmm.h_step_remap: wrong indices used for E.zz
ebfret.ui.MainWindow: fixed run button disabled on load
ebfret.analysis.hmm.run_vbayes: fix unit batch size check
ebfret.ui.Mainwindow: Improve photo-bleaching removal

* Thresholding is now done using a window-averaged signal
* It is now possible to threshold by sum of donor and acceptor