UI - Centralized default editors registration into a service

Display conditions - Added more test operators 
Display conditions - Implemented operator selection
Display conditions - Implemented property selection and rules

src/Artemis.UI/DataModelVisualization/Input/StringDataModelInputViewModel.cs

@@ -0,0 +1,15 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using Artemis.Core.Plugins.Abstract.DataModels.Attributes;
+using Artemis.UI.Shared.DataModelVisualization;
+
+namespace Artemis.UI.DataModelVisualization.Input
+{
+    public class StringDataModelInputViewModel : DataModelInputViewModel<string>
+    {
+        public StringDataModelInputViewModel(DataModelPropertyAttribute description, string initialValue) : base(description, initialValue)
+        {
+        }
+    }
+}