0.3

• Extracted the Is and IsSome typeclasses into a separate library "lawful-conversions"
• Restored the IsomorphicTo typeclass from the 0.1 design without restoring the String instance and the showAs utility

0.2

• IsomorphicTo renamed to Is
• IsSome is introduced as a parent class to it
• to moved to IsSome
• showAs dropped
• String isomorphism instances for textual types dropped, since they were not exactly isomorphisms
• IsSome instances added for String for textual types