Fix parent of class declaration.

[MikuAuahDark]

For anyone who uses this script for latest love-api, the class declaration may have no parent.

Emmy-love-api/genEmmyAPI.lua

Lines 74 to 75 in f9b1855

	if type.parenttype then
	code = code .. ' : ' .. type.parenttype

Changing that line to this

if type.supertypes and type.supertypes[1] then
    code = code .. ' : ' .. type.supertypes[1]

fixes the problem.