#5 various ng-spice-17 patches

[Dan McMahill]

Attached are a small handful of patches against
ng-spice-17. The quick summary is:

- renames makeidx to ngmakeidx. Removes the remaining
name conflicts with spice straight from berkely.

- adds a handful of missing headers in various spots.
You may wish to surround the <sys/ioctl.h> and also the
<stdlib.h> with an autoconf check.

- protects a couple of macros against being redefined.

- adds the missing INFO-DIR stuff to the ngspice.info file.

This gets rid of all but one of the various compiler
warnings I got with gcc3 on NetBSD-2.0.2/alpha.

-Dan

[Dan McMahill]

patches for ng-spice-17