Make timeout values configurable in settings

[MurzNN]

Synapse server often becomes not very fast to reply, so in bridge instances we see the timeout errors like [bot-sdk-MatrixLiteClient] error: (REQ-4) RequestError: Timeout awaiting 'request' for 60000ms.
As I quickly lookup in code, all timeout values are hard-coded?
Will be good to have ability to increase timeout values in bridge config yaml file, is this hard to implement?

Because of those timeout errors, we have issues like https://github.com/innereq/mx-puppet-vk/issues/5