Add an ability to control gm-jobs tool debug level

gm-jobs verbosity is now hardcoded and there are some debug messages on stdout instead of stderr

Tool STDERR (hardcoded level)

Ability to pass verbosity level via command line argument will improve usability and allows to pass-through any gm-jobs errors thought arcctl wrapper.

[root ~]# /usr/libexec/arc/gm-jobs 1>/dev/null
[2018-05-14 16:20:54] [Arc.GMConfig] [INFO] [3556/18980880] 	Session root dir : /home/grid/scratch
[2018-05-14 16:20:54] [Arc.GMConfig] [INFO] [3556/18980880] 	Control dir      : /var/spool/nordugrid/jobstatus
[2018-05-14 16:20:54] [Arc.GMConfig] [INFO] [3556/18980880] 	default LRMS     : pbs
[2018-05-14 16:20:54] [Arc.GMConfig] [INFO] [3556/18980880] 	default queue    : (empty)
[2018-05-14 16:20:54] [Arc.GMConfig] [INFO] [3556/18980880] 	default ttl      : 1210000
[2018-05-14 16:20:54] [Arc.GMConfig] [INFO] [3556/18980880] 	Cache            : /home/grid/cache
[2018-05-14 16:20:54] [Arc.GMConfig] [INFO] [3556/18980880] 	Cache cleaning enabled

Tool STDOUT (debug in output)

Please also move debug output from stdout to logger subsystem.

[root ~]# /usr/libexec/arc/gm-jobs 2>/dev/null | grep -v Job
Using configuration at /etc/arc.conf
Looking for current jobs