* lisp/use-package/use-package-core.el (use-package-vc-prefer-newest): User option to prefer the latest commit (as opposed to the latest release) of a package. (use-package-normalize--vc-arg): Check for use-package-vc-prefer-newest. * doc/misc/use-package.texi (Install package): Document use-package-vc-prefer-newest. * etc/NEWS: Document use-package-vc-prefer-newest.