New ways of joining instances for homesteads and guild halls.

[Quench.7091]

When it comes to dungeons/fractals/raid instances, it's easy to motivate players to party together into the same instance. They'll walk right up to that portal! It's a little more difficult to motivate players to party together for things like home instances or invite players into guild halls as guests who are outside of the guild, due to how zoning into an instance works for these instances. There are currently steps like needing to visit the instance portal on a specific map to join as a group within an instance. I think we should see additional ways to visit player homes and guild halls.

Here's a couple of ideas:

• Direct party/squad invitations and requests. Right-click a player and invite them or request to join while inside of a homestead or guild hall instance, even if they aren't on your map when you zone in.
• Join a guild members homestead through the guild UI or homestead portal. Makes guild members feel more neighborly in how they can visit you.
• A public browser for joining a homestead or guild hall, sorted by the current population in the instance. The current LFG tool would work okay on homesteads, but I think a specific browser would work really well for guild halls. Right now guild halls are mostly empty, so having visitors would be interesting. Eventually homesteads might cool down and have players desire such a feature too.