Version strings

[Matthew Selsky]

On Mon, Jan 08, 2018 at 01:41:49PM -0800, Hal Murray via devel wrote:
> >> Maybe it's time to move ntpviz and the logging
> >> stuff to a separate package.
> 
> > How does that help?
> 
> Then they could have their own version string policy rather than getting 
> tangled up with ntpsec's policy and library.
> 
> I think I'd call it a bug if a script only uses the python library to get the 
> version string.

What if we put the version string in waf, and them embed that in the generated python files in the build folder using subst_fun()?  Then we won't need to load ntpc.so, just to get the version information.

We can still get the version string from auto-revision.sh, for now.  Long-term, I'd like to simplify and just do the same git checks within waf itself.

If there are no objections, I'll work on an MR tonight and send it out to the list for review.