Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

Fix structure of new tests (r268794) for usr.bin/units.

- Make sure the tests go into the right directory. The location was
wrong so they were overwriting the bin/chown tests!
- Use the right naming scheme for the test program.
- Remove the svn:executable property from the shell script.