Unify onOpen and onDrag, and support more cases
Unify onOpen and onDrag, and support more cases

I don't think it matters whether the open comes from onOpen (opening
magnet, .torrent file, dragging file to dock, menu item) or from
dragging to the window.

These should use the same code path. The only relevant information is
the page of the app that we're on.

This change unifies the two methods, and supports dragging .torrent
files or creating a torrent when the player is active, if the dragged
files are not .srt or .vtt. We go back to the list, or to the create
torrent page in these situations, so it's not confusing for the user.

Always close open modals when handling an open.

feross/webtorrent-app,webtorrent/webtorrent-desktop,yciabaud/webtorrent-desktop,feross/webtorrent-app,feross/webtorrent-desktop,feross/webtorrent-desktop,webtorrent/webtorrent-desktop,michaelgeorgeattard/webtorrent-desktop,yciabaud/webtorrent-desktop,webtorrent/webtorrent-desktop,feross/webtorrent-desktop,feross/webtorrent-app,michaelgeorgeattard/webtorrent-desktop,yciabaud/webtorrent-desktop,michaelgeorgeattard/webtorrent-desktop