Publish v1.4.0 (facebook#954)

* v1.4.0

* Lock files

* Update CHANGELOG.md

* chore: add missing PR not included in CHANGELOG.md

* chore: fix changelog typo

* chore: fix CHANGELOG

* nits

Convert Docusaurus banner image into SVG (facebook#915)

* replaced readme header image

Changed from .PNG to .SVG to eliminate blurriness on high-resolution screens

* compressed header .SVG

* Replaced header image in blog post

Blogpost: Introducing Docusaurus

v1.3.3 (facebook#912)

* v1.3.3

* nits changelog

* run npm update & yarn update

* run prettier

Update CHANGELOG.md

Publish v1.2.1 (facebook#785)

Publish v1.2.0 (facebook#753)

Publish v1.1.5 (facebook#707)

1.1.4