Feature Request: configurable timeouts in Network.Browser

It would be very nice, especially for lambdabot (where it's more important to get a fast answer than to get one at all), to be able to configure the connection timeout for HTTP requests, preferably with sub-second resolution.

Start by locating the Network.Browser request and connection-timeout handling, then inspect how HTTP requests are configured and tested in this package. Determine where a configurable timeout belongs and how sub-second values should be represented. Done means callers, including lambdabot, can set a connection timeout with sub-second resolution and the relevant tests pass.

Written by the indexing model from the issue text.