Counts the number of files in a directoryhttps://www.monitoringexchange.org/inventory/Check-Plugins/Operating-Systems/Linux/count_file
Use this plugin to count the number of files in a directory and
issue a warning or critical state if the number exceeds a limit.
Useful if you want to monitor for example:
* a directory which contains error files and must stay empty
* a tmp dir which have to stay under a practical limit