Move usage section into own site

[Shinigami92]

Currently the usage section takes too much space from the getting started page
We would like to move, improve and maybe restructure it

There should be also its own usage link below "Getting Started"

[ST-DDT]

For clarification.

The "Getting started" page consists of multiple separate section that could be their own page, this might even be true for the usage's individual subsections.
Pages shouldn't be too small of their own, because scrolling is easier than switching to the next page.

There are however parts that are irrelevant to JS (such as Environment/implementations in other programming languages) and thus could be moved to a separate page.

---

In general, I'm not sure what this issue entails exactly or how useful this is.