Scheduler: on TRACE mode when closing connection, validate cs.

When trace mode is enabled through --trace, when the Scheduler will
close a connection, verify that no client_session associated exists
to the Scheduler entry, this condition may happen on bad API usage
by plugins.

Signed-off-by: Eduardo Silva <eduardo@monkey.io>
Epoll: move READ message after signal condition

Signed-off-by: Eduardo Silva <eduardo@monkey.io>
Core: new '-t' option to override TransportLayer from command line

Signed-off-by: Eduardo Silva <eduardo@monkey.io>
Merge branch 'master' of github.com:monkey/monkey