Add UnBan command

Reverses existing Ban command
-Added UnBanCommand class
-Added UnBanUser procedure to IChatServices.cs
-Added UnBanUser procedure to ChatServices.cs
Ban Self Message

-Added message to users who try to ban themselves
IsBanned query command

Added isbanned command
usage:
/isbanned > shows all banned users
/isbanned username > shows if a specific user is banned
Added proper notification for ban/unban/isbanned

Added proper user notification for:
- ban
- unban
- isbanned
Changing group of IsBanned

IsBanned was showing up in the global commands, should be admin only,
changed group for admin.
Adding refs to proj file

Adding compile references to JabbR.csproj
+ IsBannedCommand.cs
+ UnBanCommand.cs