Add package-config generation frontend

[sladyn98]

This PR aims to add the front-end capabilities to generate the packager-config.yml.
Some decisions I took regarding the plugin storage.
a) I decided to make use of the local storage to store the plugins json array so that we can access it throughout the session, I wanted to make use of cookies but having a too large cookie would slow down performance so the Mozilla docs suggested going with local storage is fine .
b) Also I decided to not go with the props callback function method to pass data from child to parent instead went with the basic onClick={() => this.clickChild() methods, because we were not really passing data from child to parent instead just let the child component in this case pluginCards.js make the saving call to the localStorage API.

Another descision I had to make was make use of a modal while dispaying the form required for user data, I wanted to initally go for a separate page, but since this action was anyway going to be invoked on user action and would be only accessible by this page, I realised that a modal would be a good choice. Since I was working with react-strap using a modal became quite easy

[kwhetstone]

I'm fine with the modal window, and you can get some extra feedback at the stage 1 demo next week. There could potentially be a lot of scrolling regardless of the option chosen which might be the thing people dislike the most.