allow bypassing announce queue

[HamletDuFromage]

When adding a torrent to a client with a lot of torrents, its announce (as far as I understand) is pushed to the end of a queue that could take a while to be processed.

As a workaround if I need to leech immediately, I'd just restart my client and the newer torrents would be added at the top of the queue, but it's rather inelegant.

I'd like a flag for force re-announce to bypass that queue for the torrent to start faster. This PR compiles, but I'm not familiar with the codebase whatsoever so this might not be the appropriate approach. For instance, I'm not sure about how this may or may not be related to https://www.libtorrent.org/reference-Torrent_Handle.html#queue_position_top()

This is more of a feature request than a PR

[arvidn]

it should probably also be incorporated with "connection boost", so newly added torrents take priority over existing ones, for the first announce

[HamletDuFromage]

I don't think I understand what connection boost is or does tbh

[arvidn]

I made a slightly tweaked version of this idea, here: https://github.com/arvidn/libtorrent/pull/8054

[HamletDuFromage]

neato!