Add ability to use different converters via factory

[ArtDu]

To use mappers for custom behavior

MessagePackMapper valueMapper = client.getConfig().getMessagePackMapper();

ResultMapperFactoryFactory factory =
    client.getResultMapperFactoryFactory();
CallResultMapper callReturnMapper = factory.createMapper()
            .withSingleValueConverter(
                factory.createMapper()
                    .withArrayValueToTarantoolTupleResultConverter(valueMapper, null)
                    .withRowsMetadataToTarantoolTupleResultMapper(valueMapper, null)
                    .buildMessagePackMapper(valueMapper.copy())
            )
            .buildCallResultMapper(valueMapper.copy());

Object crudResult =
    client.call("crud.select", Collections.singletonList("test_space"), returnMapper).join();
assertTrue(crudResult instanceof TarantoolTupleResultImpl);
Object boxResult =
    client.call("select_request_counters", new ArrayList<>(), returnMapper).join();
assertTrue(boxResult instanceof TarantoolTupleResultImpl);
Object primitiveObject = client.call("returning_number", new ArrayList<>(), callReturnMapper).join();
assertEquals(2, primitiveObject);

I haven't forgotten about:

• Tests
• Changelog
• Documentation
• Commit messages comply with the guideline
• Cleanup the code for review. See checklist

Related issues:
Closes #320

[akudiyar]

I like the idea in general. Let's correct the API a bit and add some short examples in the Javadocs for the people to be able to use it and read this code.

We will need to explain what that hierarchy of mappers represents actually, how it is mapped to a real result from the server.

[akudiyar]

Javadoc is missing. I suggest putting short builder usage example in the Javadoc

[ArtDu]

Added something

[akudiyar]

Looks like a copy-paste, should it be a DefaultMessagePackMapper?

[ArtDu]

I fixed something

[akudiyar]

In this example, we have valueMapper passed 3 times and one time with a necessary copy() call. We will never have a chance to explain how to use this to the customers, and we will make mistakes ourselves.

But let's pass the valueMapper once to the builder:

CallResultMapper callReturnMapper = factory.createMapper(valueMapper)
            .withSingleValueConverter(
                factory.createMapper(valueMapper)
                    .withArrayValueToTarantoolTupleResultConverter()
                    .withRowsMetadataToTarantoolTupleResultMapper()
                    .buildMessagePackMapper()
            )
            .buildCallResultMapper();

The copy() method will be called internally where it is needed.

We can make a second createMapper() method accepting also space metadata. Passing null several times is also not comfortable.

What do you think?

[ArtDu]

Yeah, your're right. It should be more easier. I changed