Small tooling enhancements

[roxkisrover]

• Updated dev dependencies
• Removed gulp-watch (since a built-in watcher was used) and path (node has it already)
• Integrated browserslist in package.json as suggested in by a new autoprefixer
• Added nodejs v6 testing as it is an LTS release
• Fixed gulp output to console: wrong messages order and 'scss compiled...' was reported twice on build (finally something useful, huh)
  😎

[matthewhartman]

Thanks heaps Anton Nikolaenko (@roxkisrover) - That's freaking awesome!!! 👍 👍 👍