Specify special attributes in resources.json references to tell if they should be excluded etc

[kennethlynne]

Refactor resources.json.

    "external": [
      "bower_components/log/log.js"
    ],
    "externalExcludeFromBuild": [
      "bower_components/angular-mocks/angular-mocks*.js"
    ],

Should rather become

    "external": [
      "bower_components/log/log.js",
      "[ no-build | no-min ]bower_components/angular-mocks/angular-mocks*.js"
    ]