Version 0.4.0

Added features:

1. Added support for Or field type. the validation will pass if any of the subtypes pass the validation

Version 0.3.0

Added features:

1. Now the Schema object is Marshallable and it can be backed up as a JSON object to be restored for future needs.

v0.2.1

Add documentation comments to types and functions.

v0.2.0

Add Null field feature

v0.1.0

docs: add docs and add schema constructor (#19)