Add support for basic types

[janjakubnanista]

This includes:

• primitives (number, string, boolean)
• arrays
• tuples
• classes (using instanceof keyword)
• interface types (defined both using interface and type keywords)
• string based Record types
• union types
• intersection types
• conditional types
• generics
• functions (Note: due to the nature of JavaScript it is not possible to check the return type of a function. What is checked is the typeof the value)

What is not included:

• number based Record types
• Date checks based on instanceof keyword