* circular gradient module
* Shadow module added
* fixed minor documentation error
* fixed small errors
* added test for shadow module
* updated shadow module to receive x and y inputs
* final shadow module with two inputs
* fixed test for shadow module
Co-authored-by: Harsh Khandeparkar <34770591+HarshKhandeparkar@users.noreply.github.com>
Co-authored-by: Jeffrey Warren <jeff@unterbahn.com>
