Core/Spells: rewrite Eclipse system

sql/updates/world/custom/custom_2018_07_07_01_world.sql

@@ -0,0 +1,8 @@
+DELETE FROM `spell_script_names` WHERE `spell_id` IN
+('spell_dru_eclipse_lunar',
+'spell_dru_eclipse_solar',
+'spell_dru_eclipse');
+
+INSERT INTO `spell_script_names` (`spell_id`, `ScriptName`) VALUES
+(48517, 'spell_dru_eclipse'),
+(48518, 'spell_dru_eclipse');