no timeout on requests

[aniche]

code uses python requests library
https://requests.readthedocs.io/en/master/user/quickstart/
mentions: "You can tell Requests to stop waiting for a response after a given number of seconds with the timeout parameter. Nearly all production code should use this parameter in nearly all requests. Failure to do so can cause your program to hang indefinitely"

This in fact happened to us with your api this week
please add timeout to "requests" calls in client.py

[aniche]

#8

[laurynas]

@aniche Thanks for the PR! Merged and released 1.5.0 version.