fix(regexp): Use js compatible regexp instead of positive lookbehind

[uesteibar]

It seems positive lookbehind is not supported in javascript, so we need to use capturing parenthesis

Fixes #11

@michaelwayman if you could have a look at this and check it works fine for you, that would be awesome ❤️

Instructions

Go to your hyper plugins folder

cd ~/.hyper_plugins/local

Clone the repository

git clone --depth=1 git@github.com:uesteibar/hyperdocs.git

Install dependencies

cd hyperdocs
npm install

Add to your .hyper.js file

localPlugins: ['hyperdocs']

And refresh your terminal.