Import ztest.1 man page.

Create a nroff man page for ZoL from:

  http://grml.org/online-docs/ztest.1.html

Which itself was derived from:

  http://opensolaris.org/os/community/zfs/ztest/

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #518
Create mount.zfs, zinject, and zpios man pages.

And update the automake templates to install them.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #518