Quartz confguration with RHPAM is missing clustering guide.

In earlier release(BPMS 6.x) we have included steps to configure quartz with BPMS[1] but in RHPAM 7 this configuration is missing. Include quartz configuration steps in RHPAM 7 documentation.

[1] https://access.redhat.com/documentation/en-us/red_hat_jboss_bpm_suite/6.4/html/installation_guide/chap_testing_the_installation#setting_up_quartz