Added and mounted to the session a trasport adapter in the constructor.

Requests use transport adapters to define and maintain connections.
Http adapter has a parametr max_retries - maximum number of retries
each connetion shoult attempt when connection fails. Due to default
max_retries=0 after the connection faluire/closure/timeout/other
reason no other retries are permitted and BadStatusline error is
raised. In order to avvoid this issue number of retries were increased.