[vaadin-charts] Missing removePane() method

Hi,
This probably needs a ticket, but I'll raise it here first before going to Trac...

In the Vaadin Charts v3.1 Configuration class is the option to addPane() for things like gauges etc.
But there is no corresponding removePane() method to clear the (single-item) list.

This is a problem as, in our current use-case, the configuration gets re-used for changing chart types - i.e. a base class creates the configuration, then it gets changed by sub-classes when the chart type changes.

While you're doing the refactoring (e.g. for the widht typo) can you please add a public void removePane() and/or removeAllPanes() so as to keep the getter/setter java nice and clean?
[Note: although the javadoc states Pane is only relevant for Polar and angular gauges, the Highcharts js still draws it even if it's a column!]

Many thanks,
Peter

It's probably also worth noting that addPane() is a bit misleading..the getPane() only retruns the first element (if there is one).
This should be refactored to setPane() so it's clear. If this is future plans to support multiple panes. great, but then getPane() should include an index...
Thanks,
Peter