Move docs to github pages

[Steveb-p]

Documentation in current form, while works great, requires traversing "source code" of repository. It might be beneficial to use gh-pages to show documentation only.

It should be little cost to enable it. As a matter of fact, @makasim you can already do so in repository settings by going to https://github.com/php-enqueue/enqueue-dev/settings and choosing /docs from master as gh-pages source. Conveniently .md files can be used and Github uses Jekyll to build the site.

I've taken the liberty and enabled it on my own repository and added a custom theme, which allows creating sidebar menu (for a relatively complex docs structure should be a nice addition - see 2. refence below). Link to template is available so you can see if "white" colour scheme is more to your liking.

See: https://steveb-p.github.io/enqueue-dev/

References:
https://help.github.com/en/articles/user-organization-and-project-pages
https://pmarsceill.github.io/just-the-docs/

When enabled, gh-pages will show under:
https://enqueue-php.github.com/enqueue-dev
(unless you make a organization repository names enqueue-php)

[Steveb-p]

I f... up and accidentally pushed into this repository instead of my own (for template testing for enqueue github pages). I've force pushed master back into previous state, but you might want @makasim to enable strict checks against pushing to master:

[makasim]

I f... up and accidentally pushed into this repository instead of my own (for template testing for enqueue github pages).

Few people have access to the repo. The restriction would make their life harder. It does not bother me much, at least now. Let's keep it as is.

[makasim]

Good idea with gh pages. I'll give it a try.

[Steveb-p]

@makasim If you don't mind I'll simply give you colabolator status on the fork, so you'll be able to check how it looks without affecting current master branch (since afaik you can either have gh-pages branch, master branch in root, or master branch in /docs). I've also added instructions on how to run documentation locally with docker.

EDIT: Done so.
https://github.com/Steveb-p/enqueue-dev
https://github.com/Steveb-p/enqueue-dev/blob/master/docs/index.md#contributing-to-this-documentation

Other themes you can check at https://help.github.com/en/articles/adding-a-jekyll-theme-to-your-github-pages-site if you prefer something different.

[Steveb-p]

@makasim You'll probably need to enable github pages in https://github.com/php-enqueue/php-enqueue settings for github to pick up the pages. It should show master branch specifically, without /docs subdirectory.

[makasim]

fixed