Serialization/deserialization

Topics
	How to use (de)serialization
	Shows basic use of the calls to serialize and deserialize.
	Serialization of user types
	Shows how to implement serialization for custom user types.
	Serialization overview
	Shows how user-provided functions fit into ryml's structure.
	Serialization for Tree
	Shows ryml's default implementation of tree serialization.
	Serialization for nodes
	Shows ryml's default implementation of node serialization.
	Scalar charconv helpers
	These functions are used by the parser and emitter to convert scalars to and from chars.

Detailed Description