Allow parameterless commands to build correctly

Resolves #253

src/Discord.Net.Commands/Command.cs

@@ -38,7 +38,15 @@ namespace Discord.Commands
                 _instance = instance;
 
                 Name = source.Name;
-                Text = groupPrefix + attribute.Text;
+
+                if (attribute.Text == null)
+                    Text = groupPrefix;
+
+                if (groupPrefix != "")
+                    groupPrefix += " ";
+
+                if (attribute.Text != null)
+                    Text = groupPrefix + attribute.Text;
 
                 var aliasesBuilder = ImmutableArray.CreateBuilder<string>();
 

src/Discord.Net.Commands/Module.cs

@@ -48,8 +48,6 @@ namespace Discord.Commands
 
         private void SearchClass(TypeInfo parentType, object instance, List<Command> commands, string groupPrefix, IDependencyMap dependencyMap)
         {
-            if (groupPrefix != "")
-                groupPrefix += " ";
             foreach (var method in parentType.DeclaredMethods)
             {
                 var cmdAttr = method.GetCustomAttribute<CommandAttribute>();
@@ -63,9 +61,15 @@ namespace Discord.Commands
                 {
                     string nextGroupPrefix;
                     if (groupAttrib.Prefix != null)
+                    {
+                        if (groupPrefix != "")
+                            groupPrefix += " ";
                         nextGroupPrefix = groupPrefix + groupAttrib.Prefix ?? type.Name;
+                    }
                     else
+                    {
                         nextGroupPrefix = groupPrefix;
+                    }
                     SearchClass(type, ReflectionUtils.CreateObject(type, Service, dependencyMap), commands, nextGroupPrefix, dependencyMap);
                 }
             }