Fixed race conditions in ambient artillery and aviation modules that were causing error spam in server logs.

Updated keys

- Updated start-up delay to eliminate race condition between BFM and ALiVE Opcom initialisation.

- Minor tweaks to remove erroneous errors at startup
- Removed conflict between BFM-MapObj and ALiVE Mil placement modules

- Fixed minor bug in "Ambient Aviation" module

Significant re-work of how BFM handles terrain objectives:

The map is meshed with a hexagonal array of circles whose radii are defined by the user. Every circle is given a base score derived from

- number of buildings
- number of roads (weighted per road type)
- amount of vegetation

Every front update, all of the objectives get given a weighting factor that is computed from its distance from the front line. The objectives then get a new priority which is the product of their base score and their front weighting. The objectives are sorted into descending order and then only the top objectives are actually given to the commander. As the front moves through the map grid the different objectives get turned "on" and "off" as they bubble up into the top 50 most valuable points on the map.

- Major code restructure to distribute front line calculations over multiple frames; Improves performance and reduces desync in multiplayer scenarios.

- Removed a piece of un-used legacy code that was producing nuisance errors.

- Fixed significant errors in the "Front Update" code that was causing the simulation to get "stuck".

- Added "Custom ALiVE Settings" module to allow custom settings for virtual unit simulation. Virtual combat rate, virtual combat range and virtual unit movement speed may be set to any number, outside of the 25%, 50%, 75%, 100%, 150%, 200% options in the ALiVE modules

- Removed "Custom OPCOM Settings" module, because it doesn't work. The module still exists in the modules list to allow backward compatibility with existing missions, but doesn't do anything. This module should be deleted from any mission it was used in.

- Repaired broken "Ambient Aviation" module.

- Removed re-weighting / re-ordering of objectives after front update as it was found to be breaking the OPCOMS. A solution is being sought.