Connections optimization (requests pool_connections, pool_maxsize)

[litnimax]

In http_client.py we have the following:

class SynchronousHttpClient(HttpClient):
    """Synchronous HTTP client implementation.
    """

    def __init__(self):
        self.session = requests.Session()
        self.authenticator = None
        self.websockets = set()

So every requests creates a new connection.
What if we add there connection pooling and caching? Something like this:

def __init__(self):
        from requests.adapters import HTTPAdapter
        self.session = requests.Session()
        self.session.mount('http://', HTTPAdapter(pool_connections=50, pool_maxsize=100))
        self.authenticator = None
        self.websockets = set()

But we need a way to pass these parameters when we initialize ari client.
What do you think?