Add vendors

[Vlek]

For vendors, instead of having a list of items on the screen like normal muds where it gets dumped into the mud output, we can add them to rich tables so we can have sub menus and stuff.

[Vlek]

When a player buys or sells an item, it should output a command to the console that the user could have instead used instead of navigating the table system. This will prompt them to be able to do so in the future if they wished or use within aliases.