MFC r232365:

Provide pre/post transfer method callbacks for icbbb
clients.

These are helful when making certain drivers work on both Linux
and FreeBSD without changing the code flow too much.

Reviewed by:	kib, wlosh
Approved by:	kan@
MFC r254379:

Avoid potential redefinition of the macro.
MFC r262499, r262505, r262507, r262509:

r262499:
  release.sh:
  - Add a VCSCMD variable that defaults to 'svn checkout',
    and update places 'svn co' is used directly.
  - After sourcing a configuration file, prefix SRCBRANCH,
    PORTBRANCH, and DOCBRANCH with the SVNROOT.
  - Properly capitalize 'FreeBSD.org' in the default SVNROOT.
  - Update Copyright.

  release.conf.sample:
  - Add an example to use git instead of svn, by nullifying
    SVNROOT, and setting SRCBRANCH, DOCBRANCH, and PORTBRANCH
    to the URL fo a git repository.

  release.7:
  - Document VCSCMD.

r262505:
  In release/Makefile, remove exclusion of CVS directories in the
  src/ and ports/ distributions.

  While I am thinking about it, exclude .git directories for src/
  and ports/, as somewhat of a followup to r262499.

r262507:
  Chase r262505, and remove CVS exclusion from picobsd builds.

r262509:
  Rework how WORLD_FLAGS and KERNEL_FLAGS are set, to remove an
  unnecessary expr(1) call.

Sponsored by:	The FreeBSD Foundation
MFC	r262678;
ufs: small formatting fixes.

Cleanup some extra space.
Use of tabs vs. spaces.
No functional change.

Reviewed by:	mckusick
MFC: r262494

Rough cleanup (new sentence -> new line, grammar, spelling, mdoc).
This could use more work.

PR:             187035 (in part)
Submitted by:   Bjorn Heidotting
[automated] Merge in upstream-github/stable/9

Conflicts:
	release/Makefile