code: private String getRenderedBody(final ResponseDefinition response) {
          final String templatePath = fileSource.getPath().concat("/" + response.getBodyFileName());
          final Template template = Velocity.getTemplate(templatePath);
          StringWriter writer = new StringWriter();
          template.merge(context, writer);
          final String rendered = String.valueOf(writer.getBuffer());
          return rendered;
      }
docs: Renders the velocity template.
  
  @param response the response definition