[svn] Applied John Daily <jdaily@cyberdude.com>'s patch for his "quad" commands ...

[svn] Applied John Daily <jdaily@cyberdude.com>'s patch for his "quad" commands (which
I renamed to "lockable_boolean") in the .wgetrc (currently just passive_ftp).
Wrote documentation for his changes and added the missing "referer" to the
.wgetrc section (making mention of the issue of "referrer" being the correct
spelling).