Add bot categories and rework bot saving [setups]

[splewis]

Bots should be able to be grouped similarly to grenade categories.

Rather than combine the use of commands (.save and .cats), I'll likely try to use separate commands and treat it a little differently, i.e.:

• place a few .bots
• .savesetup <name>
• .loadsetup <name>
• .setups would then list those that are saved

This would likely replace the current all-or-nothing bot saving, which doesn't work very well.

[skliffmueller]

#115

Needs to be tested

[skliffmueller]

It's done and tested. Ready for pull.