Simulate headers on enum values in SlotContainerEditor (#49)

* Simulate headers on enum values in SlotContainerEditor

* Update CHANGELOG.md

Co-authored-by: Julien Fryer <[email protected]>
# Conflicts:
#	com.unity.visualeffectgraph/CHANGELOG.md

Author: iTris666

com.unity.visualeffectgraph/CHANGELOG.md

@@ -126,6 +126,7 @@ The version number for this package has increased due to a version update of a r
 - De-nicified attribute name (conserve case) in Set Custom Attribute title
 - Changed the default "No Asset" message when opening the visual effect graph window
 - Subgraphs are not in hardcoded categories anymore : updated default subgraph templates + Samples to add meaningful categories.
+- Enum fields having headers show the header in the inspector as well.
 
 ## [7.1.1] - 2019-09-05
 ### Added

com.unity.visualeffectgraph/Editor/Inspector/VFXSlotContainerEditor.cs

@@ -95,6 +95,11 @@ public virtual void DoInspectorGUI()
                 enumNames = values.Select(t => new GUIContent(Enum.GetName(prop.Key.FieldType, t))).ToArray();
                 enumValues = values.ToArray();
 
+                HeaderAttribute attr = prop.Key.GetCustomAttributes<HeaderAttribute>().FirstOrDefault();
+
+                if( attr != null)
+                    GUILayout.Label( attr.header, EditorStyles.boldLabel);
+
                 EditorGUILayout.IntPopup(prop.Value,enumNames,enumValues );
             }
             else