Merge async_* network support into emper

For beehive I would like to use the thread blocking anomaly avoidance mechanism introduced by Burak.

I don't care about detection or mitigation nor for disk I/O. All I need are the epoll based async_* network functions.
Unfortunatly Burak's branch still uses cmake and I don't understand the individual commits enough to cherry-pick only my desired functionality.
What is the best way to get async network suppport into master? Should I try to rebase Burak's whole branch? Or try to separate and prepare only the bits I actually care about?