new upstream release

Update monit to 5.5.1

from 5.5.1 CHANGES
> Version 5.5.1
> 
> IMPROVEMENTS:
> 
> * Info and debug messages are no longer sent to stderr, only to stdout.
>   Thanks to Sergey Kirpitchev for initial patch.
> 
> * Improved output from 'check program', If the program returns an error
>   message, include only that message in alert $DESCRIPTION so users can
>   compose their own alert format. If program provided no output on
>   error, use a default message.
> 
> * Improved "check system", $HOST can now be used as a service name.
>   $HOST will expand to the system hostname. Example: check system $HOST
> 
> BUGFIXES:
> 
> * Fixed "Unable to read magic" which was reported on first Monit start.