Descbot should use plexchar data

[jonrober]

We should use character data from the plexchar files to at least do an alternate list of characters based on character ownership, as well as do something around displaying tag data in descbot. Here are some starting thoughts:

• Character ownership and listings should be done by the plexchar data, with a "*" or similar to denote the characters we have descriptions for.
• Being able to show and list characters by tags should be supported.
• Perhaps descs should be brought entirely into that data tree? The only problem is that the plexchar data is suited for characters and not places, which leaves some of the data barren.

[jonrober]

Not adapted quite this way, on looking at things. Instead I've added a new Character bot that provides the character ownership and tag data. The 'problem' is that descbot provides things like places instead, and that gets confusing. Since we're not actually updating any of that information, it's possible we might want to just add legacy character descriptions into Character bot in some fashion, then deprecate Descbot for our own default setup.