Move hard-coded TOSCA types out of the Java code and into a configuration file.

The abstract class org.onap.aai.babel.xml.generator.model.Model has a hard-coded Map named typeToModel which stores the mappings from the TOSCA type(s) to an internal Java bean.
For example, the TOSCA type org.openecomp.resource.vf.allottedResource is mapped to an AllotedResource object.
Similarly TOSCA types with a prefix of org.openecomp.cp are mapped to the LIntfWidget.

These TOSCA type strings (currently all matching org.openecomp.*) are not configurable. Moving these mappings to an external configuration file will make it easier to modify and extend Babel's mapping functionality.