[z2670] Proper implement script for Zum'rah - Zul'Farrak

(based on commit 5323bd8)

Signed-off-by: Xfurry <xfurry@scriptdev2.com>

(based on commit SD2-TBC[s2728] - 12f73a7)

Signed-off-by: Schmoozerd <schmoozerd@scriptdev2.com>
[z2671] Some small improvements to Zum'Rah

* Rename a function to fit better to needs
* Alter behaviour to work properly in case a grave is looted while the enocunter is in progress
* Do not use currently looted graves by Zum'Rah

(based on commit 4d36785)

Signed-off-by: Xfurry <xfurry@scriptdev2.com>

(based on commit SD2-TBC[s2729] - caa03c3)

Signed-off-by: Schmoozerd <schmoozerd@scriptdev2.com>