Add utility method to adapt a Supplier to a Randomizer

[fmbenhassine]

As of v3.8, it is possible to use a Supplier as a Randomizer transparently thanks to a dynamic proxy created by random beans. However, this feature (introduced in #28) made the API verbose because we need to explicitly specify the type of the lambda expression when using EnhancedRandomBuilder#randomize. Here is an example:

EnhancedRandom enhancedRandom = EnhancedRandomBuilder.aNewEnhancedRandomBuilder()
                .randomize(String.class, (Randomizer<String>) () -> "foo")
                .build();

This is due to the fact the EnhancedRandomBuilder#randomize is overloaded with both a Randomizer and a Supplier.

IMO, this explicit cast is verbose and can be avoided by letting the user adapts the supplier if any. RB would provide a static method to create the proxy. This simple inversion of roles makes the API and its usage less verbose without compromising the feature.