Merge ModelsBuilder in, NuGet dies on circ dependencies now

src/Umbraco.ModelsBuilder/ModelsNamespaceAttribute.cs

@@ -0,0 +1,16 @@
+using System;
+
+namespace Umbraco.ModelsBuilder
+{
+    /// <summary>
+    /// Indicates the models namespace.
+    /// </summary>
+    /// <remarks>Will override anything else that might come from settings.</remarks>
+    [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = false, Inherited = false)]
+    public sealed class ModelsNamespaceAttribute : Attribute
+    {
+        public ModelsNamespaceAttribute(string modelsNamespace)
+        {}
+    }
+}
+