Revised methods and new tests
More tweaks, improvements
Fix merge failures
Make DynamoViewModel a property in WorkspaceViewModel
Added new icons to DynamoCore
created CustomNodeIcon on StartPage
Add model file
Another test for nested family instance
Change as feedback
Rename GCAnonymousSymbols() to GCSymbols() and some cleanup
Remove callsite gc root
Update test cases for verifying reference count
Using RuntimeMemory.PushFrameForGlobals() to extend stack for global variables
Handle the case that expected value is null
Icons complete, nice HierarchicalDataTemplate organization
GC deactivated symbols
Fix test cases
Implemented temporary storage for custom node GraphSyncData
Fix test cases
Updated CustomNodeDefinition.Compile to remove scheduler related code