svgelements does not process Metadata

[tatarize]

Metadata is always display=none which tends to exclude it from being a proper element. If processed it could not be parsed as svg 2.0 spec removes any requirements as to how this data should be parsed. While RDF is standard it's not a requirement, processing metadata may simply require enforcing the Metadata is display as None and therefore non-rendered and therefore omitted from the parsed tree.

[Sophist-UK]

I am unclear what is contained in metadata and whether it actually needs to be parsed, however at a minimum we should save metadata so that it can be reinserted into an SVG file on save - in which case we need to have some way of updating e.g. coordinates if a transform matrix is changed.