nodejs-generator-gulp-angular: version bump 0.5.1 -> 0.6.0

  * Breaking Change Directory structure evolved to the recommendations from
    the Angular team. Do not run this version of the generator on an existing
    project generated with a previous version
  * Isolation of the proxy middleware, some fixes and disabling by default
  * Minifying HTML (index, not the partials)
  * Thanks to @intellix, @marani and special thanks to @zckrs wich join me
    as commiter