Add metadata documentation (#2547)
Add metadata documentation (#2547)

* Create metadata.md

* Update the table

* Added builderAliases

* Updated aliases

* Added relative links + should not mentions

* Notes edits

* Remove authors note

* Rename file

Also changed the header levels to accomodate the new title/purpose

* Added introduction

* Revert "Added introduction"

This reverts commit 98005b1475289bdc1487b18301bb729a00443fc9.

* Sorry, signature problems

* Make some sentences a little bit more clear

* Solve necessity typo
Modernizr/Modernizr,Modernizr/Modernizr