Fix bug in debug SendOpcode command
Credits to Laizerox, evilwow, Neo, and Schmoozerd
Merge pull request #72 from LeFroid/Rel19

[Core] Apply updates
Merge remote-tracking branch 'upstream/Rel19' into Rel19
[Core] Implement some of the spell effects used in Yogg Saron encounter
Target limit and effect for 63744, 63745 and 63747
Target limit for 62978
Stacking exception for 65157 and 64775
[c12675] Credit to @xfurry
[Core] All units can have Not_Selectable flag while boarded on vehicle
Thanks to debilvul and xfurry
[c12676]
[Core] Make use of GROUP_UPDATE_FLAG_VEHICLE_SEAT
Original patch by thenecromancer (TC)
Credit to xfurry [c12677]