[lmi] Allow switching skin while lmi is running

[Greg Chicares]

See
  https://github.com/vadz/lmi/pull/27
and in particular
  
https://github.com/vadz/lmi/pull/27/commits/e56e18ba4cb91622a2bc674710e8422899284c31
pushed 20160529T2316Z b27a3af..1436cf2 .

Now we have
  ce_product_name.?pp
  ce_skin_name.?pp
and the first determines its enumerators in
  product_names.?pp
while the second does that in an unnamed namespace in the 'ce_' source.

I'd like to determine the enumerators in a parallel location for both:
that makes code review and future maintenance easier. Do you *strongly*
prefer that I not create new
  skin_names.?pp
files?