History for Customizers

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Customizers are DataManagers that extend DataSkins which are not stored in [Racks].  They act as DataPlugIns for CustomizerFolders.  

On the "Meta Types" tab of a Customizer, you can select what meta-types the Customizer will be used for.  Once active, any DataSkins which are accessed from the Customizer Folder or its children will use it as their data manager, as long as the !DataSkin is of one of the chosen meta-types.  (Unless of course a customizer in a folder nearer the dataskin supports that meta-type.) DataSkins will query their customizer for attributes and propertysheets, as well as notifying it of add, change, and delete operations through DataManagementEvents.