Separate timeout for connect() and call()

[wosiu]

My use-case:
If I connect to server, I want to know that there is something wrong immediately.
However when I call my client, I want to wait longer, as my calculation in RPC server logic takes a while.
The best would be to be able to provide timeout kwarg to call() method, so that a developer can specify separate timeouts for each call.
Question is, how timeout parameter in call method should be set as a default. 2 ideas:

1. whatever, like 10 sec
2. None. In that case timeout which was used for creating Client is used for call as it is done right now - backward compatibility provided.

I may try to develop something and PR, but let me know first what do you think plz.