Create a separate pCampbot "disconnect" console command which disconnects connected bots.

"quit" console command now requires bots to be separate disconnected first before quitting.
This is to prepare the way for disconnecting/reconnecting different numbers of bots in a pCampbot session.
And hopefully resolves bug where console appears not to be reset if Environment.Exit(0) is called on a different thread
Make it possible to disconnected a specified number of bots via the pCampbot console command "disconnect [<n>]"

Bots disconnected are ascending from last in numeric order.
Temporarily no way to reconnect bots.
refactor: restructure pCampbot multi-bot connection code.
refactor: start bot connection thread within BotManager rather than externally
Make it possible to reconnect pCampbots with the console command "connect [<n>]".

If no n is given then all available bots are connected
Add -connect (-c) switch to pCampbot command line options.

Now, bots will only connect at startup if this switch is specified.
If it is not specified, then a separate "connect" command is required on the pCampbot command line
Add pCampbot console commands to sit all bots on ground and stand all bots
Add experimental "sit user name" and "stand user name" console commands in SitStandCommandsModule.

"sit user name" will currently only sit the given avatar on prims which have a sit target set and are not already sat upon.
Chiefly for debug purposes.
Add --regex options to "sit user name" and "stand user name" console commands to sit/stand many avatars at once.

Currently, first name and last name are input separate but are concatenated with a space in the middle to form a regex.
So to sit all bots with the first name "ima", for instance, the command is "sit user name --regex ima .*"