Bug fixes & Misc:
-- Map crashed because empty item_combo script (bugreport:8959)
-- Wrong MATK calculation of Distort Crescent/Zangetsu effect (SC_ZANGETSU) (bugreport:8998)
-- Wrong damage reduction of Sera's Pain Killer effect (SC_PAIN_KILLER) (bugreport:8994)
-- Fixed Shape Shift (NC_SHAPESHIFT) wrong requirement (bugreport:9002)
-- @itembound, getitembound usage. Not, now allowed for unspecified bound_type (thank Ceejay Abne! http://rathena.org/board/index.php?showtopic=94726)
-- Change check behavior for skill requirement level-dependent check.
-- Removed NC_REPAIR hardcoded requirement.
-- Moved the required equipped item to 'RequiredEquipment' on skill_require_db.txt.
-- Missing "Option_Ruwach" as contantan.
-- Corrected Chasewalk STR bonus, it's SC_CHASEWALK2, different with SC_INCSTR.
-- Corrected some Rebellion skill's effects.
-- USESKILL_FAIL_MADOGEAR message for failed skill that needs player has Madogear.
-- Changed skill name and description length to 31 chars.
-- Some documentation updates.
-- Follow up 0f2dd7f. (Well, using empty password in import file, won't works, if you want, empty the original conf file. Fix this later, related on 'sscanf' for those files)
-- Follow up 28c90bb, thank @julia40124009
-- Misc. :P

Signed-off-by: Cydh Ramdh <house.bad@gmail.com>