MFC r310181 (matthew) (originally r309314):
Allow a user-overridable setting 'PKG_CMD' to control the command used
to create a repo during 'make packages'.

Sponsored by: The FreeBSD Foundation

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Merge the projects/release-pkg branch to head.

This allows packaging the base system with pkg(8), including
but not limited to providing the ability to provide upstream
binary update possibilities for non-tier-1 architectures.

This merge is a requirement of the 11.0-RELEASE, and as such,
thank you to everyone that has tested the project branch.

Documentation in build(7) etc. is still somewhat sparse, but
updates to those parts will follow.

Sponsored by: The FreeBSD Foundation

Include a 'package-pkg' target, intended for use for
architectures we do not provide upstream pkg(8) packages.

This is not tied to anything as-is, and likely will break
your system if used (based on experience with testing with
powerpc).

There is an overwhelming amount of evil happening here,
so until the issues are fixed, it will not be tied into the
'packages' target.

Sponsored by: The FreeBSD Foundation