Ability to set request HTTP timeout

[BezBartek]

Sometimes, TG partly crashes, there are communication issues or TG internal timeout does not work (no response after timeout time).

What I propose:
Give an ability to provide HTTP timeout option.
The existing timeout parameter still would be a TG internal timeout (no changes), and http_timout would be a new parameter, that will be passed to requests.request call as timeout.

Example:
conn.getVertices(..., timout=10, http_timeout=(10, 20))

Therefore:
in the library _req method, instead of:
requests.request(method, url, headers=_headers, json=_data, params=params, verify=verify)
would be:
requests.request(method, url, headers=_headers, json=_data, params=params, verify=verify, timeout=http_timeout)