Corrected skill db loading code which was using a totally wrong column count in sevreal cases (or didn't do any checks at all).
Cleaned up skill db lookup code
* added some well-behaved functions to replace macros (skill_get_index)
* used skill_get_index() to replace often occuring blocks of code that did the skill_id -> skilldb_index calculation in-line
git-svn-id: https://svn.code.sf.net/p/rathena/svn/trunk@11657 54d463be-8e91-2dee-dedb-b68131a5f0ec
f7d4427c1a