Wakeup outgoing connection selector if necessary.

Immediately wake up selector after connect trigger and
subscribe/unsubscribe write requests.
Wakeup incoming connection selector if buffer becomes available.
Don't sleep in AbstractDeserializer.

Don't wait in AbstractDeserializer if no buffer data is available from
network. IncommingConnectionThread does it already (in a better way).
use buffer immediately in deserializer if available
Merge branch 'wakeup-selector' of https://github.com/derSascha/stratosphere-streaming into github-master
Merge branch 'latency-improvements' of https://github.com/derSascha/stratosphere-streaming into github-master