Updates DynamicNode with some performance enhancements especially around things like HasProperty and GetProperty.

Also when it returned children, it was actually re-iterating over all children (going to the repo to find them even though
they were already resolved).

src/umbraco.MacroEngines/RazorDynamicNode/DynamicBackingItem.cs

@@ -88,7 +88,7 @@ namespace umbraco.MacroEngines
                     var children = media.ChildrenAsList.Value;
                     if (children != null)
                     {
-                        return children.ToList().ConvertAll(m => new DynamicBackingItem(m));
+                        return children.ConvertAll(m => new DynamicBackingItem(m));
                     }
                 }
                 return new List<DynamicBackingItem>();

src/umbraco.MacroEngines/RazorDynamicNode/DynamicNode.cs

@@ -168,7 +168,7 @@ namespace umbraco.MacroEngines
                     }
                     else
                     {
-                        _cachedChildren = new DynamicNodeList(n.ChildrenAsList);
+                        _cachedChildren = new DynamicNodeList(children);
                     }
                 }
                 return _cachedChildren;
@@ -294,34 +294,16 @@ namespace umbraco.MacroEngines
             var results = s.Search(criteria);
             return ExamineSearchUtill.ConvertSearchResultToDynamicNode(results);
         }
-
-
-
-
+        
         public bool HasProperty(string name)
         {
             if (n != null)
             {
-                try
-                {
-                    IProperty prop = n.GetProperty(name);
-                    if (prop == null)
-                    {
-                        // check for nicer support of Pascal Casing EVEN if alias is camelCasing:
-                        if (prop == null && name.Substring(0, 1).ToUpper() == name.Substring(0, 1))
-                        {
-                            prop = n.GetProperty(name.Substring(0, 1).ToLower() + name.Substring((1)));
-                        }
-                    }
-                    return (prop != null);
-                }
-                catch (Exception)
-                {
-                    return false;
-                }
+                return GetProperty(name) != null;
             }
             return false;
         }
+
         public override bool TryInvokeMember(InvokeMemberBinder binder, object[] args, out object result)
         {
             try
@@ -1347,7 +1329,43 @@ namespace umbraco.MacroEngines
         public IProperty GetProperty(string alias)
         {
             if (n == null) return null;
-            return n.GetProperty(alias);
+
+            object result;
+            IProperty prop;
+            //check the cache first!
+            if (_cachedMemberOutput.TryGetValue(alias, out result))
+            {
+                prop = result as IProperty;
+                if (prop != null)
+                    return prop;
+            }
+
+            try
+            {
+                prop = n.GetProperty(alias);
+                if (prop == null)
+                {
+                    // check for nicer support of Pascal Casing EVEN if alias is camelCasing:
+                    if (alias.Substring(0, 1).ToUpper() == alias.Substring(0, 1))
+                    {
+                        //change the alias to the other case to check
+                        alias = alias.Substring(0, 1).ToLower() + alias.Substring((1));
+                        prop = n.GetProperty(alias);
+                    }
+                }
+            }
+            catch (Exception)
+            {
+                return null;
+            }
+
+            if (prop == null)
+                return null;
+
+            //cache it!
+            _cachedMemberOutput.TryAdd(alias, prop);
+
+            return prop;
         }
         public IProperty GetProperty(string alias, bool recursive)
         {