Added plugin descriptions to plugin list

[RunDevelopment]

This adds plugin descriptions to the plugin list on the website.

Screenshot

My intention is to make plugins more accessible. I have a feeling that many users miss plugins or only know the really popular ones (Line numbers).

So to make the function of plugins more visible, I added the description of every plugin to the list, so users can broadly understand what a plugin is supposed to do; the name alone simply isn't enough. For further information, they can then click the link and read more.

The description of a plugin is the short paragraph every plugin page has, summarizing the plugin. For example, the desc of Auoloader is "Automatically loads the needed languages to highlight the code blocks". I extracted every one of them and put them into components.json, so it's accessible from various parts of the website (and because it's easy).

To avoid redundancy and because the header of every plugin can now be generated, I added a little script to do just that. The header of every plugin is now a one-liner and scripts/code.js will add everything.