* Remove and replace OnEndOfDay() ref
* Restore functionality of obsolete EOD, waiting for deprecation in August 2021
* Cleanup
* Adjustments to only post message when using obsolete EOD
* nit, extra space
* Address review
* Adjust test to reflect new behaviour
* Move GetPythonArgCount to an extension method
* Add unit test
* nit accidental import
* Refactor broken test
* Use Py.GIL() state for extension
This includes updating all usages of symbol as a security identifier to use the new type.
The type includes a unique field, SID, as well as the current ticker's value. This allows
for consistent addressability while also allowing the ticker to evolve over time with the
mapping changes.
Effort was made to maintain compile and runtime backwards compatibility.