teiiddes-2190: Initial commit of REST importer to support generating transformations for REST web services as sources that take dynamic parameters.
Merge pull request #383 from tejones/teiiddes-2190

teiiddes-2190
TEIIDDES-2207: Correct Web Service issue when view lacks a primary key

* When a view model lacks a primary key, the model lacks an input element

* WebServiceBuilderHelper
 * Refactor the SQL generation function to only create declarations and
   assignment if the model has any input elements.
 * Removes default 'example' SQL since this is not valid and likely to
   provide nothing but confusion to users

* SQLStringVisitor
 * Avoids possible NPE when the object list is null