Update to latest LibVLC 4.0 API

Update libVLC event and libVLC media list so as to be able to bump to latest libVLC API.

This pull request also refactor event dispatching into a struct table so as to avoid repeating the attach/detach with the same parameters.

This should probably be merged right before !57 (merged) so as to bump the libVLC API in incremental and non-breaking order.

approved this merge request

added Feature VLC Core labels

merged

mentioned in issue #422 (closed)

mentioned in merge request !45 (closed)

assigned to @fkuehne

changed milestone to %4.0