Ignore splay time on SIGUSR1

If the agent is configured to use splay, receiving a SIGUSR1 while
beeing in the splay loop will cause the agent to wait and instantly
run as documented.

The agent now skips the splay sleep when the signal is received.
Merge branch 'b1-systems-fix_signal_handler'

* b1-systems-fix_signal_handler:
  Ignore splay time on SIGUSR1

closes #1453