Guild hall basics revamp

Commit 1: New Combat Settings
- Restructured hall combat rules with a new CheckGuildHallAttack function. This allows a player in a GuildHall class room to attack *any* player who is not a guildmate or ally. Combat and kills are not penalized with outlaw or murderer status. This solves a couple age-old awkward hall combat issues (like an innocent getting into a hall and defenders being forced to go outlaw). This also allows anyone to participate in hall combat without safety issues. Meanwhile, the safety still functions for guildmates and allies, so multitarget spells work as normal.

Commit 2: Subsequent changes
- Flipping the switch no longer outlaws a player
- Conquering a hall no longer outlaws a player
- Unguildeds and immature guild members can now flip the switch
- Player portals re-allowed in halls
- Prisms cannot be bound to halls (so portals cannot have halls as destinations). While I was in there, I also made prisms non-decay and non-sweepable. Odd that an item that must be put on the ground would not already have these traits.

This is all done with the intent to streamline guild halls so that additions may be made. I hope to try something with permanent portals inside halls as part of an incentive for guilds to buy and use halls for mobility purposes. Will also look at regearing options and other things to help guilds that rooms and mules cannot offer.