Generate a callsite identifier associated with each callsite

Generate a unique string name for a callsite that appears in every node
Address coding standards
Defect fix: MAGN-3605 and MAGN-3646
Added comments
DynamoPaths packages into roaming appdata.
Drop "dynamo" from packages subdirectory name.
Retarget packageloader at DynamoPaths.Packages
Update package download folder path.
Update sample tests packages path.
Ensure path setup before controller construction.
Added test case for defect MAGN-3648
Updated test case for defect MAGN_3603 as API was deprecated
Remove dead code in core
Minor code fixes
Removed deprecated code
Function renamed
Move definitions folder to appdata.

Refactor resolution of Dynamo's appdata folder into a separate method.
Remove a dead comment.
Construct CustomNodeManager with definitions path.
Create definitions and packages if they don't exist.