Added new command line arguments to the agent executable.
Added new command line arguments to the agent executable.

The new command line arguments will have running the agent as
standalone program or as a daemon and allow changing the
location of the PID file without code modification.

The change was done is order to support both Fedora and RHEL
distributions.

Change-Id: I42bba6b7e498e4f5a6c725a4693b7234d700a1c6

silenceli/oga-windows,edwardbadboy/ovirtagent-ubuntu,oVirt/ovirt-guest-agent,silenceli/oga-windows,oVirt/ovirt-guest-agent,edwardbadboy/ovirtagent-ubuntu,oVirt/ovirt-guest-agent,edwardbadboy/ovirtagent-ubuntu,silenceli/oga-windows,edwardbadboy/ovirtagent-ubuntu,silenceli/oga-windows,oVirt/ovirt-guest-agent