Lootdrop Filtering Adjustments

[Akkadius]

• Add new logging category "Loot"
• Adds fields npc_min_level and npc_max_level to lootdrop_entries which runs checks against the current NPC as long as the field values are non-zero
• Fields minlevel and maxlevel are renamed to trivial_min_level and trivial_max_level respectively for lootdrop_entries for item drops to be filtered based on the player level
• Before, trivial_max_level defaulted to 127 in the database, this became an issue on some servers and some scenarios, the default has been adjusted to simply be 0 and only check if the value is non-zero

[xackery]

closes #1104