v0.7.0
730: Prepare 0.7 release r=Xaeroxe a=Xaeroxe Closes #677 Closes #553 @Rhuagh I also added the note you requested to README.md <!-- Reviewable:start --> --- This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/amethyst/amethyst/730) <!-- Reviewable:end --> Co-authored-by: Jacob Kiesel <[email protected]>