Several token and endpoint bugfixes

src/Discord.Net/API/DiscordRawClient.cs

@@ -57,18 +57,21 @@ namespace Discord.API
         {
             AuthTokenType = tokenType;
 
-            switch (tokenType)
+            if (token != null)
             {
-                case TokenType.Bot:
-                    token = $"Bot {token}";
-                    break;
-                case TokenType.Bearer:
-                    token = $"Bearer {token}";
-                    break;
-                case TokenType.User:
-                    break;
-                default:
-                    throw new ArgumentException("Unknown oauth token type", nameof(tokenType));
+                switch (tokenType)
+                {
+                    case TokenType.Bot:
+                        token = $"Bot {token}";
+                        break;
+                    case TokenType.Bearer:
+                        token = $"Bearer {token}";
+                        break;
+                    case TokenType.User:
+                        break;
+                    default:
+                        throw new ArgumentException("Unknown oauth token type", nameof(tokenType));
+                }
             }
 
             _restClient.SetHeader("authorization", token);
@@ -485,7 +488,7 @@ namespace Discord.API
             while (true)
             {
                 int runLimit = (limit >= DiscordConfig.MaxUsersPerBatch) ? DiscordConfig.MaxUsersPerBatch : limit;
-                string endpoint = $"guild/{guildId}/members?limit={limit}&offset={offset}";
+                string endpoint = $"guild/{guildId}/members?limit={runLimit}&offset={offset}";
                 var models = await Send<GuildMember[]>("GET", endpoint).ConfigureAwait(false);
 
                 //Was this an empty batch?

src/Discord.Net/Net/Rest/DefaultRestClient.cs

@@ -52,7 +52,8 @@ namespace Discord.Net.Rest
         public void SetHeader(string key, string value)
         {
             _client.DefaultRequestHeaders.Remove(key);
-            _client.DefaultRequestHeaders.Add(key, value);
+            if (value != null)
+                _client.DefaultRequestHeaders.Add(key, value);
         }
 
         public async Task<Stream> Send(string method, string endpoint, string json = null, bool headerOnly = false)

src/Discord.Net/Rest/DiscordClient.cs

@@ -43,6 +43,7 @@ namespace Discord.Rest
             _connectionLock = new SemaphoreSlim(1, 1);
             _log = new LogManager(config.LogLevel);
             _userAgent = DiscordConfig.UserAgent;
+            BaseClient = new API.DiscordRawClient(_restClientProvider, _cancelTokenSource.Token);
 
             _log.Message += (s,e) => Log.Raise(this, e);
         }
@@ -72,7 +73,6 @@ namespace Discord.Rest
             try
             {
                 var cancelTokenSource = new CancellationTokenSource();
-                BaseClient = new API.DiscordRawClient(_restClientProvider, cancelTokenSource.Token);
 
                 var args = new LoginParams { Email = email, Password = password };
                 await BaseClient.Login(args).ConfigureAwait(false);
@@ -87,7 +87,6 @@ namespace Discord.Rest
             try
             {
                 var cancelTokenSource = new CancellationTokenSource();                
-                BaseClient = new API.DiscordRawClient(_restClientProvider, cancelTokenSource.Token);
 
                 BaseClient.SetToken(tokenType, token);
                 await CompleteLogin(cancelTokenSource, validateToken).ConfigureAwait(false);
@@ -126,7 +125,7 @@ namespace Discord.Rest
                 catch { }
             }
 
-            BaseClient = null;
+            BaseClient.SetToken(TokenType.User, null);
             _currentUser = null;
 
             if (wasLoggedIn)
@@ -186,7 +185,7 @@ namespace Discord.Rest
         {
             var model = await BaseClient.GetGuildEmbed(id).ConfigureAwait(false);
             if (model != null)
-                return new GuildEmbed(this, model);
+                return new GuildEmbed(model);
             return null;
         }
         public async Task<IEnumerable<UserGuild>> GetGuilds()