removed.)
Add rebuild_whatisdb weekly variable that defaults to NO.
This is for running makewhatis weekly.
This defaults to NO because it is not needed using just base sets/default
install which provide the whatis.db file(s).
consistent with what FreeBSD uses /etc/defaults for and since SVR4
uses /etc/default for another purpose. as discussed on tech-userlevel,
and no objections were made.