Added script for checking Ulimit for users

Will allow to check ulimit usage for a specific user, currently supporting the glassfish user.

There are a few manual commands that will be sycofied together with the glassfish installation to make it a default monitoring script for the glassfish suite.

Also fixed a typo in the check_temp script that would cause wrong perfdata to be sent.
Made the glassfish user a variable instead for easier re-use in the file.