[Mercs] Add Mercenary Support (#2745)

* [Mercs] Add Mercenary Support

# Notes
- Adds `--merc-tables` support to database dumper.
- Adds Mercenary-based repositories.
- Adds required SQL `2023_01_15_merc_data.sql` to insert the tables for those who don't already have them.
- Adds optional SQL `2023_01_15_merc_liaisons.sql` to change NPCs to the Mercenary Liaison class optionally.

* Inline.

* Trim tables_to_dump output

Co-authored-by: Akkadius <akkadius1@gmail.com>

utils/sql/git/optional/2023_01_15_merc_liaisons.sql

@@ -0,0 +1,3 @@
+UPDATE `npc_types`
+SET `class` = 71
+WHERE `lastname` LIKE '%Mercenary Liaison';