Motivation
If we receive an early HTTP response, the last action on a HTTP/1.1
connection is to send the .end message. While we had an error handling
path in the code, it wasn't tested, and when executed it would end up
leaking the connection by failing to close it _or_ return it to the
pool.
This patch fixes the issue by appropriately terminating the connection
and adding a test.
Modifications
Add a test
Terminate the connection if sendEnd fails
Result
Fewer connection leaks
Same fix for HTTP/1 that landed for HTTP/2 in #558.
### Motivation
`HTTP1ClientChannelHandler` currently does not tolerate immediate write errors.
### Changes
Make `HTTP1ClientChannelHandler` resilient to failing writes.
### Result
Less crashes in AHC HTTP/1.
- a new `RequestOptions` struct was created, that can be used to set request specific options. It is required by the `HTTPExecutableRequest`
- Added support for `ignoreUncleanSSLShutdown` in the `HTTPRequestStateMachine` and the `HTTP1ConnectionStateMachine`. In http/2 `ignoreUncleanSSLShutdown` is always off.
David Nadoba
Cory Benfield
Fabian Fett
