Use timeout with leastSize on TCPConnection

[tchaloupka]

I'm not exactly sure about this, but I guess that if one sets the read timeout on the TCPConnection it should be used in this blocking call too so it won't block forever.

[s-ludwig]

Agreed about the timeout. It should throw an exception in that case, though, because otherwise leastSize would signal a connection close with 0 bytes returned.

[tchaloupka]

I've modified the asyncAwaitAny with timeout parameter to return if Waitable completed in time or not and then used it in waitForData.

Let me know if it's ok this way.

[s-ludwig]

The main problem is that waitForData may not throw in case of a timeout, I've opened a PR with an alternative implementation that I had lying around for a while: #159 With this, leastSize simply has to enforce(ret != WaitForDataStatus.timeout).

[s-ludwig]

Okay, #159 is in now.