Allow setting custom retries number/timeout/ssl settings for connectors.

[Pilipets]

There are various reasons when sending requests are gonna fail - the idea of this suggestion is allowing low-level retries/timeouts for HTTP requests if possible on the bundle.
Also, I noticed, that SSL is enabled in boost::beast by default, though disabled in CPR (the CPR allows it) - uniform behavior is expected, in my opinion. Enabling/disabling SSL configurations will be a valuable addition.

When creating the connector, one can specify those connection parameters.
connector::cpr_blocking_monadic connector(token); // for simple usage as it's now
connector::cpr_blocking_monadic connector(config); // here config is CPR-related class, which allows advanced configuring.

Looks like httplib, CPR already supports timeouts - https://github.com/yhirose/cpp-httplib, https://github.com/whoshuu/cpr; in boost/beast you are setting 30 seconds as constants.
Regarding retries, one might say the programmer should handle it on the upper level. Indeed one can, but won't it create a performance overhead because of the serialization/deserialization taking place?

[Smertig]

I'll add setters to all connectors (SSL, timeouts, etc..)

Regarding retries, one might say the programmer should handle it on the upper level. Indeed one can, but won't it create a performance overhead because of the serialization/deserialization taking place?

That's a good point. We need a way to pass pre-serialized arguments.