* Fixes#2445 and fixes#2446.
* Fixed shadow refiner.
— The script uses the values of the array instead of the indexes to loop through it.
* Fixed segfault in getequiprefinecost.
— No checks in getequiprefinecost meant there were possibilities using negative indexes in arrays.
* Added to the script documentation what happens on failure when calling getequiprefinecost (it returns -1).
Thanks to @vstmpf, @crazystorm2017, and @hendra814!
* Converted refine_db.txt to refine_db.yml
* Refine success rates can now be set in refine_db.yml. rAthena's default NPCs will respect this database by default.
* Added shadow equipment refiner
Thanks to @Akkarinage @aleos89 @Atemo and @Mikegyver for their inputs.
