Added script command 'cooking' to activate this window and applied it to the 5 cooking kit items.
Renamed the cooking quest variable to cooking_q to avoid a naming collision with the new script command.
(You need to manually rename all occurences of this variable in your txt-savefile/sql-database if you want to preserve player progress.)
The code still relies on the messy skill_produce_mix logic and still uses completely custom equations. To be fixed in a separate commit.
git-svn-id: https://svn.code.sf.net/p/rathena/svn/trunk@13628 54d463be-8e91-2dee-dedb-b68131a5f0ec
71fbf3e1a4