Changed data types into thin wrappers around a Key-Value tree.

This breaks AbilityActionCollection, which should also become a thin wrapper around the Key-Value tree.
Updated KVLib and fixed warnings
Fix a crash when trying to assign to a property that doesn't have a property already assigned to it.
Added functionality to StartPage links
New Addon... and Load Addon.. now has proper functionality
Only need to add functionality to recent addons links to be done with
issues #36
Fixed UnloadUnits after changes to DotaData lists
Fixed ObjectInfo crashing when creating a new dotadataobject
#34 Custom objects can be created. Currently, only Object.BaseClass and Object.ClassName are set. At some point, creating an object should add a node to the object browser rather than calling RefreshTreeView, and the new object should maybe be automatically opened.
Updated the CreateObjectDialog to comply with new DotaDataObject constructors.