Revise installation locations for BIND binaries

This moves all but named binaries from ${sbindir} to ${bindir}.

Most BIND binaries are not necessary administrative programs, nor daemons and in many cases can be used by users and thus does not belong to /usr/sbin.

Case can be made that even named can be run by user, but at least on Linux it seems to be the case that daemons are /usr/sbin.

Closes #1724 (closed).