Minor: Switch syntax from `Optional<Wrapped>` to `Wrapped?`
Minor: Switch syntax from `Optional<Wrapped>` to `Wrapped?`

* For consistency with Swift's built-in `??` operator function, using operator forms of optionals in args:  
	⁃ `Optional<Wrapped>`→`Wrapped?`  
	⁃ `ImplicitlyUnwrappedOptional<Wrapped>`→`Wrapped!`

capnslipp/NilCoalescingAssignmentOperators,capnslipp/NilCoalescingAssignmentOperators