Log message:
Pre-create directories used in the do-install target.

Log message:
Style nit -- use a shell for loop instead of a bmake .for loop.

Log message:
Honor PKGMANDIR.

Log message:
Import dtach from pkgsrc-wip.  Packaged by Francis Gudin.

dtach is a tiny program that emulates the detach feature of screen,
allowing you to run a program in an environment that is protected from
the controlling terminal and attach to it later.  dtach does not keep
track of the contents of the screen, and thus works best with programs
that know how to redraw themselves.