Add command: /sector_chmod_range

[Erth Paradine]

Request/Goal:
Extend upon code from pre-existing routines /sector_chmod and /load_sector_range, to add support for specifying ranges to /sector_chmod, through a new command: /sector_chmod_range

Currently:
In order to designate a particular region (range) of space as + peace, + protected, etc... The admin most manually determine the appropriate octree coordinates for each and every related sector. This is an error-prone and tedious process, which is better facilitated by the game engine itself, using logic which already exists within the admin command framework.

Result of proposed:

• Greatly eases the process of adding and maintaining trade/safe/build/combat zones in various regions of space.

Suggested Method:
Merge relevant pre-existing logic from /sector_chmod and /load_sector_range.

Retain all existing chmod options: peace/protected/noenter/noexit/noindications/nofploss

Rationale:

• This eases administrative tasks, such as the process of establishing and maintaining designated zones (build, no combat, no NPCs, etc).
• Retaining support for noenter/noexit with a range command is valuable when seeking to manage ship movement mechanics, and their relationships to locked-down build or combat sectors. The other chmod options are also equally valuable, but mostly self-explanatory as to why ranges are good for them.

Credits:
This is an expansion of an earlier suggestion's alternative approach, which further integrates a more specific suggestion from Ghent96 .