MAGETWO-40129: M2 GitHub Update (version 1.0.0-beta)

MAGETWO-33538: M2 GitHub Update (version 0.74.0-beta16)

MAGETWO-33537: M2 GitHub Update (version 0.74.0-beta15)

MAGETWO-33536: M2 GitHub Update (version 0.74.0-beta14)

Merge branch 'develop' of https://github.com/magento/magento2 into MA…

…GETWO-33535

Merge remote-tracking branch 'pub/develop' into MAGETWO-33534

MAGETWO-33533: M2 GitHub Update (version 0.74.0-beta11)

MAGETWO-33532: M2 GitHub Update (version 0.74.0-beta10)

MAGETWO-33531: M2 GitHub Update (version 0.74.0-beta9)

- update version with git grep --name-only '0.74.0-beta8' | grep -v 'CHANGELOG.md' | xargs -i@ sed -i 's/0.74.0-beta8/0.74.0-beta9/g' @
- update changelog and composer.lock

MAGETWO-33530: M2 GitHub Update (version 0.74.0-beta8)

 - add changelog