Expand guide on using ColumnSchemas in creating custom primitives

While converting Primitives to use Woodwork for their input and return types, there seems to be some common optimizations that can/should be used to define the best input and return types for a primitives.

There isn't much discussion of _how_ a user can ensure that they're following these principles. In the woodwork in featuretools guide, the concept of how `ColumnSchemas` get used as input and return types is explained, but the Feature Primitives doc, might be the best place to explain how to best use `ColumnSchema` objects.

The tips I can think of right now are:
- Specify the most specific return type as possible. So if you know it'll be an integer, specify that instead of just the `'numeric'` tag
- It's better to specify nullable return types, as they won't result in errors during feature matrix calculation
- If specifying a Logical Type in return types, you should also specify any desired standard tags (like `'numeric'` for a `Double` feature) to allow them to be considered for generic numeric inputs (ColumnSchema objects won't implicitly add the `'numeric'` tag - that's an accessor behavior)