Support for pgpool2-compatible postgres driver

[AntonOfTheWoods]

asyncpg doesn't support pgpool2, whereas aiopg seems to have enough support for using broadcaster.

I will try and find the time to create a PR

[AntonOfTheWoods]

@tomchristie , I'm not sure I understand why this is a discussion not an issue/feature request. To be honest, I thought you had abandoned the project, so was putting it here as a discussion point for exchange with others who might want pgpool-compatible pub-sub, rather than as a request you might help with implementing! Sorry!

[tomchristie]

No need to apologise. Have just started to roll out discussions across a bunch of the encode projects, and am starting to try to move towards them being the first point of engagement. (With "Issues" reserved for verified bugs and feature requests that have been discussed and okayed.)

[AntonOfTheWoods]

Perfect, thanks. So do you have an opinion/comment? :)

[tomchristie]

Personally, nope. I don't have enough bandwidth myself to have an opinion on that right now.

[AntonOfTheWoods]

I exchanged with the pgpool2 team and initial testing appears that the problem with asyncpg has been worked around, and will be available in the upcoming versions of both the 4.1 and 4.2 branches of pgpool2.

So we can "close" this.