While the whole idea of calling these functions through the MainWindow
instance is atrocious, until we change the architecture of all this
refreshProfile() is a useful function to have.
In order to make this cleaner to implement I allowed an argument to
ProfileWidget's replot() which allows picking a specific dive. By
defaulting this to 0 we get the previous behavior when calling replot()
without an argument.
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>