New failure detection algorithm for ng_one2many.

[Evgeny Dolgopiat]

>>Evgeny Dolgopiat:
>>
>>I wrote new failure detection algorithm based on heartbeat signal for
>>ng_one2many node. Features:
>>
>>- automatic detection of failures;
>>- automatic detection of recoveries;
>>- detection of point of failure (see diagnostics in man page);
>>- configurable timing parameters of failure and recovery detection;
>>- you can create your own heartbeat packet or use default;
>>- you can set your rules for detecting that incoming packet is hearbeat  
>>packet;
>>- heartbeat algorithm can be used for different network layers (not only 
>>ethernet layer).
>
>Is it possible to turn it off so that it wouldn't work at all?
>
>rik

Failure detection could be turned off by control messages of ng_one2many.
It didn't break default behaviour. It is turned off by default. See man page 
for details.