new configuration settings

All, 

Anyone relying on the nightly snapshot will want to know about the new
configuration settings:

        --disable-libiconv, forces FreeTDS to use its built-in libiconv

We had two settings that defaulted to "yes".  The "right" way to handle
them is to have them appear as "disable" switches (because it's implied
that if you don't set a switch, its converse will take effect).  If you
try "./configure --help", you'll see:

        --disable-threadsafe instead of enable-threadsafe [default yes]
        --disable-debug instead of enable-debug [default yes]

These enable/disable things are flexible:

        --disable-threadsafe
        --enable-threadsafe=no

were and are both accepted.  

N.B. For anyone fooling with configure.in, it turns out we can (and
should) use shell comments more than we do. We've been leaning too heavily
on m4 comments:  

http://www.gnu.org/manual/autoconf/html_chapter/autoconf_9.html#SEC106

--jkl