Fix mainLoop() link in docs.
Fix mainLoop() link in docs.

mesos/chronos,lionelnicolas/chronos,vixns/chronos,motusllc/chronos,motusllc/chronos,motusllc/chronos,motusllc/chronos,mesos/chronos,vixns/chronos,mesos/chronos,mesos/chronos,vixns/chronos,lionelnicolas/chronos,vixns/chronos,lionelnicolas/chronos,lionelnicolas/chronos