OptionsDialog, StatsDialog, MainWindow

OptionsDialog - settings now linked to MainWindowPanel
statsdialog - divorced from pylab for now, started showing overall
statistics in new object StatsDialog
MainWindowPanel - catches ZeroDivisionError when calculating percentage
MainWindow - writes data to new file userdata.db on wx.EVT_CLOSE (i.e.
closing the window)
MainWindow & TrainingWindow - resized for prettiness (including golden
ratio :-) )