Changes

Added new built-in plugins for special cases values:
- Infinity
- NaN
- undefined

Breaking changes

Reworked configuration management

Configuration is now managed by the .config property on the serializer instance.
Removed version property from serialized object.

This property was already unused and was taking space on the serialized object making it
heavier for nothing.
Removed built-in plugin for null, value will be inserted as native JSON's null value.
Plugins are now middlewares, deferring the roles to them to identify if a value should be
serialized instead of leaving the job to the serializer