Add mappings between equivalent Smalltalk <-> Java types

[mattys101]

The basic Java Wrapper implementation assumes PrimObjects have a javaValue that can be unwrapped. Moreover, return values are wrapped by instances of Java without taking into account whether an appropriate Smalltalk type exists.

A means of mapping Smalltalk types to java types needs to be included to, in particular, support the appropriate wrapping of basic types when they are provided as return values from calling a Java method. For example:

• java.lang.String -> smalltalk String
• int/java.lang.Integer -> smalltalk Integer
• boolean/java.lang.Boolean -> smalltalk true/false
• null -> nil
• etc.