Add backers and sponsors from Open Collective (#2700)
Add backers and sponsors from Open Collective (#2700)

This is for your open collective backers and sponsors to appear directly on your README. 
see how it'll look [here](https://github.com/apex/apex#backers)
[More info](https://github.com/opencollective/opencollective/wiki/Github-banner)

Also add badges on top.
jadejs/then-jade,pugjs/jade,pugjs/pug,pugjs/then-jade,jadejs/then-jade,pugjs/jade,pugjs/then-jade,pugjs/pug