Entity manager 3.0.0

• Use HammerID instead of the entity index (Fix #1)
• Fix crash due to missing adminmenu plugin
• Remove console variables

To convert old configs to new ones, follow these steps:

1. Stop the server
2. Make a backup of the configs/entity-manager folder
3. Make sure that you have all the maps for which the config file is available
4. Remove the old entity-manager (v2.*) plugin
5. Install the entity-manager-v2-to-v3.smx plugin
6. Install the hammer-id-generator
7. Start the server
8. Wait until the plugin stops showing activity
9. Stop the server
10. Remove the entity-manager-v2-to-v3.smx plugin
11. Install the new entity-manager (v3.*) plugin
12. Start the server