message: Bump CLI version to 1.7.4
diff: {
  "name": "polymer-cli",
  - "version": "1.7.3",
  + "version": "1.7.4",
  "description": "A commandline tool for Polymer projects",
  "homepage": "https://github.com/Polymer/tools/tree/master/packages/cli",
  "repository": "github:Polymer/tools",
  