[client-keepalive] validate client keepalive settings
[client-keepalive] client specific keepalive thresholds
[client-keepalive] client specific keepalive handler/s
[client-keepalive] test the feature, has_key? fixes
[client-keepalive] threshold hash severity order
Merge pull request #518 from portertech/client-keepalive

Client specific keepalive thresholds & handlers