LIBOMV-630: TestClient improvements (patch by Kephra Nurmi)

Improved TestClient:
added '@' as a command prefix to target one avatar only and to check, if a named avatar is logged in.

Improved TestClient to add new commands:

groupmembers GroupnameOrUUID - shows groupmembers UUIDs
grouproles GroupnameOrUUID - shows grouproles UUID and Names
invitegroup AvatarUUID GroupUUID RoleUUID* - invites an avatar into a group (without querying groupmembers first !-)

added public Dictionary<UUID, Group> GroupsCache = null; to TestClient.cs to refactor copy and paste code of group commands.
added friend.UUID to output of FriendsCommand.cs
swapped output of UUID and name in GroupsCommand.cs



git-svn-id: http://libopenmetaverse.googlecode.com/svn/libopenmetaverse/trunk@2989 52acb1d6-8a22-11de-b505-999d5b087335

Programs/examples/TestClient/Commands/Groups/InviteGroupCommand.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using OpenMetaverse;
+using OpenMetaverse.Packets;
+using System.Text;
+
+namespace OpenMetaverse.TestClient
+{
+    public class InviteGroupCommand : Command
+    {
+        public InviteGroupCommand(TestClient testClient)
+        {
+            Name = "invitegroup";
+            Description = "invite an avatar into a group. Usage: invitegroup AvatarUUID GroupUUID RoleUUID*";
+            Category = CommandCategory.Groups;
+        }
+
+        public override string Execute(string[] args, UUID fromAgentID)
+        {
+            if (args.Length < 2)
+                return Description;
+
+            UUID avatar = UUID.Zero;
+            UUID group = UUID.Zero;
+            UUID role = UUID.Zero;
+            List<UUID> roles = new List<UUID>();
+
+            if (!UUID.TryParse(args[0], out avatar))
+                    return "parse error avatar UUID";
+            if (!UUID.TryParse(args[1], out group))
+                    return "parse error group UUID";
+            for (int i = 2; i < args.Length; i++)
+                if (UUID.TryParse(args[i], out role))
+                    roles.Add(role);
+                
+            Client.Groups.Invite(group, roles, avatar);
+
+            return "invited "+avatar+" to "+group;
+        }
+    }
+}