First iteration on mmemaligned direct I/O.

git-svn-id: svn://graphite/diminuto/trunk@481 5dfbf39a-1452-0410-8a97-9e58fedde8e3
Removing because eliminating capability.

git-svn-id: svn://graphite/diminuto/trunk@482 5dfbf39a-1452-0410-8a97-9e58fedde8e3
First iteration of wipe.

git-svn-id: svn://graphite/diminuto/trunk@483 5dfbf39a-1452-0410-8a97-9e58fedde8e3
Wipe looking pretty good testing on USB stick.

git-svn-id: svn://graphite/diminuto/trunk@484 5dfbf39a-1452-0410-8a97-9e58fedde8e3
Mostly done with wipe.

git-svn-id: svn://graphite/diminuto/trunk@485 5dfbf39a-1452-0410-8a97-9e58fedde8e3