Fix custom config with older HttpClient

Since HttpClient 4.3, custom configuration such as the connection timeout and the socket timeout are set in a `RequestConfig` object stored in the `HttpContext`.

Unfortunately, older HttpClients are not supporting this infrastructure and new clients throw an exception when the deprecated API is used.

This commit detects if the client is an "old" implementation and set the configuration through the deprecated means to restore full backward compatibility with these features.

_Note that because of the -WError flag, no import on deprecated classes are allowed which is the reason why I used FQNs_