gitignore idea-generated files.
Brief working notes regarding different types of identity-numbers.
Test for simple cases where we create Norwegian or Unknown factories.
Restructure project. Divide into:

- id-api for API and common.
- id-all parent-pom for.
- id-norway project for norwegian id-number factory.
Javadoci
Expand unit tests.
Resolve code analysis warning.
Refactoring.

- Let IdFactory be an interface again.
Extend NorwegianIdToken to give information about sex.