Add a section in the options.html page to explain the perms in manifest.json

[cliffordfajardo]

Prerequisites

• Put an X between the brackets on this line if you have done all of the following:
  • Checked that your issue isn't already filed: https://github.com/cliffordfajardo/cato/issues

Description

Several user's have requested that I explain what the permissions used in this app are for. Some non-technical folks maybe worried that the developer is doing with the permissions

It wouldn't hurt to add it to the extension page's description