* Fixed some typos on skill_copyable_db.txt that causing Shadow Slash (and other skill?) cannot be copied, bugreport:8500 http://rathena.org/board/tracker/issue-8500-plagi-buggi/
* Follow up f3bb209 also remove unused check of INF3_DIS_PLAGIA since using skill_copyable_db.txt now
* Follow up 96443cd

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