Make ConnectionInstance.js:CONNECT_TIMEOUT_MS configurable

[Nebukadneza]

As seen in #292, some networks take longer to connect to than others. One example are many IRCNet servers, for example the uni-erlangen one.

I had to manually bump the timeout in:

matrix-appservice-irc/lib/irc/ConnectionInstance.js

Line 10 in b8c784f

const CONNECT_TIMEOUT_MS = 30 * 1000; // 30s

It’d be great if this was configurable per-network in the config.

Thanks!
-Dario

[4nd3r]

before next big release, can we get this fixed, so I don't have to patchi it every release?
life with IRCnet is hard enough 😿
or at least raise the default to 60 as quick-and-easy win? pretty please 🤠