Adding this_is_rpm_install variable for template

in create_initd_startup(startup_fname, frontend_dir, glideinWMS_dir, cfg_name, is_rpm='')
Usinf the value of parameter is_rpm
By default it has value '', that enable autodiscovery in the startup script.
A value of 'yes' would create a startup script for RPM, anything else a startup script for tarballs.
unified template for tarball and RPM

Now the script can be invoked as root or the service user and the template will generate both the RPM and tarball script

SU_COMMAND su and runuser if available
invoke_as_factory/frontend (wrapper function)

used some local variables when possible

removed export for FRONTEND/FACTORY_USER - no subprocess is checking env var
left export for $HOME $X509_CERT_DIR, some python code checks $HOME

removed downtime from frontend (not reachable) only in factory

echo $”some string” -> echo “some string”

reconfig: better parameter handlin

unified usage string in both scripts
- would be good to change command syntax