Sixteenth beta for initial release

• The subwidgets input_amp_specs and input_weight_specs now round the displayed numbers to max. 3 digits. When clicking into the text field, the full precision is displayed
• "Changed specs" only appears when specs have been edited
• Dynamic signal-slot connections have been replaced by eventFilter which does not produce memory allocation faults
• Several small corrections in plot_3d
• In the tab for the impulse response, sine / rect and sawtooth stimuli can be selected and plotted as well
• The UI now has a movable splitter between input and plot widgets. Please give feedback whether this is useful or not.
• Minimum filter order is now be selected using a checkbox instead of a (single) radio button
• All modules can now be run using python -m pyfda..
• Several small bug fixes, code clean up