data type mapping

like the db type and talend type in schema
should support app type:
1. how to config, remain use XXX_mapping.xml?
2. is it possible to create a interface or helper class for each component family implement?

there also 3 points need to be considered:
1. customer type/java.util.map/... which we can't find a properly talend data type for it.
2. user endpoint type is different with API type, which type we use on app type. some application will maintains two different type, one is human readable, another is for API.
so there will be user endpoint type --> API type --> talend type
3. such as cassandra, it maintains two different type system, one is old, but we should support it.