Log message:
pkgtools/pkgchkxx: Update to 0.2

* Performance improvement: `pkgchkxx -s` no longer invokes `make update
  CLEANDEPENDS=yes` but now uses `make update
  DEPENDS_TARGET='package-install clean'`.
* Performance improvement: `pkgrrxx` by default now removes working
  directories directly instead of running `make clean`, which is slow. You
  can disable this optimization with a configure option
  `--disable-fast-clean`.
* Performance improvement: Tools now use `posix_spawn(3)` on platforms
  where it exists, and fall back to `fork` & `exec` where it doesn't.
* `pkgrrxx` now shows the number of entries in each non-empty TODO list, to
  give the user some clue about the time it's going to take.
* Fixed an issue where `RR> ` could be printed twice depending on how the
  C++ compiler optimized the code.

Log message:
pkgtools/*: revbump for libfetch

libfetch's recent behavior change can be viewed as a bugfix or as an
ABI change.  pkg_install vendors libfetch from the sources, for
bootstrapping reasons and thus needs a revbump.  For consistency and
to reduce confusion, also bump the other two packages that depend on
it.

Log message:
New package, pkgtools/pkgchkxx. From wip.

pkgchkxx and pkgrrxx are complete rewrites of pkgsrc pkg_chk and
pkg_rolling-replace respectively. These are functionally compatible but run
faster.

This implementation achieves better performance by using a faster language,
better algorithms, and making use of many CPUs whenever possible.