Core/Disables: Added DISABLE_TYPE_PHASE_AREA

[mdX7]

Tests performed:
Used the following sql and checked if any of the Refugees are visible in Stormwind harbor while gm off

DELETE FROM `disables` WHERE `sourceType`=9 AND `entry`=11595;
INSERT INTO `disables` (`sourceType`, `entry`, `flags`, `params_0`, `params_1`, `comment`) VALUES 
(9, 11595, 0, '', '', 'Disable Darnassian and Gilnean Refugees phase');

Note:
Also thought about skipping loading of objects with disabled phases entirely, but since this table is reloadable and creature/gameobject isn't i decided to just not apply the phase to the players

[Shauren]

1. Why go this ways intead of just removing phase_area?
2. Name is too generic for what it does, it disables phase_area, not the phase (still works if gained from aura)

[mdX7]

1. Why go this ways intead of just removing phase_area?

so its easier to re-enable them without looking years of commit history back to find the related phase_area lines