[s1892] Some code cleanup
[s1893] Use default SQL storage for spell_script_target
[s1894] Add support to pass spell_script_target depending on effect index

To clarify: The new column spell_script_target.inverseEffectMask stores the inverse Mask for effects,
so if you want a target to NOT fit for effect 1, you need to add 2^1 == 2 to the mask value.

Signed-off-by: Schmoozerd <schmoozerd@cmangos>