CFLAGS change

[Richard Stallman]

I just checked in a change which probably needs to have a different
interface.  The change is that optimization is turned off unless the
macro OPTIMIZE is defined.

The reason for this is that -O and inlining get in the way of
debugging.

I don't think that the macro OPTIMIZE is the right interface, though.
It is merely a quick hack.  I think optimization should be enabled by
default.  Perhaps the right interface would be a configure option,
--disable-optimization.  Would someone like to implement that?