[Xlibs] patches for Xt

[Keith Packard]

Around 18 o'clock on Jan 30, "Jeremy C. Reed" wrote:

> Can I do these few changes?

Isn't there some suitable automake magic to install Shell.h?  I think you 
just need to stick it in some appropriate list of files.  I have this
vague recollection that StringDefs.h needed custom stuff because it was 
generated.

Aside from that, we really can't install Xalloca.h unless it doesn't 
require magic autofoo magic to use.  Generating it with autoconf shouldn't 
be too hard though.

-keith