[javascript] custom configuration does not generate index.js

Description

We have a custom client configuration to generate client side stud

Swagger-codegen version

2.3.1

Swagger declaration file content or url

Client Config file looks like below

  "groupId":"com.acme.pet",
  "artifactId":"pet-client-core",
  "artifactVersion":"1.0.0",
  "artifactUrl":"https://bitbucket.org/acme/pet-client-Core",
  "artifactDescription":"Acme Pet Center client core driver",
  "licenseName":"Acme Proprietary",
  "licenseUrl":"https://acme.co",
  "scmConnection":"Acme Proprietary" ,
  "scmDeveloperConnection":"Acme Proprietary",
  "scmURL":"https://bitbucket.org/acme/pet-client-core",
  "developerName":"Acme" ,
  "developerEmail":"hello@acme.co" ,
  "developerOrganization":"Acme" ,
  "developerOrganizationUrl":"https://acme.co" ,
  "modelPackage":"com.acme.pet.models",
  "apiPackage":"com.acme.pet.apis",
  "invokerPackage":"com.acme.pet.client",
  "httpUserAgent": "Acme-DRC-Driver"
}

Command line used for generation

java -jar /usr/share/swagger/swagger-codegen.jar generate -l javascript -c pet-client-config.json -i pet.yaml

Steps to reproduce

create a config.json as mentioned above and run the above command.
Notice that javascript code generated does not have "index.js" as expected.

Related issues/PRs

Suggest a fix/enhancement

Reproduce the issue with pet-client-config.json, pet.yaml, and the documented java -jar ... generate -l javascript command. Inspect the JavaScript generation path and its templates to determine why index.js is omitted; done means the generated JavaScript client includes index.js with the custom configuration.