Support basic ad blocking (maybe through @cliqz/adblocker-electron, or another lib, or homebrew)

Description

Hello, you could block some websites advertising

Steps to Reproduce Issue

Specifications

• Version of Nativefier (run $ nativefier --version): v6.13.0
• Version of Node.js (run $ node --version): v4.4.0
• OS: windows 10
• Architecture x64
• Stack trace from the error message (if any)

<Stack trace here>