mktables: Enable -annotate arg on early Unicodes

mktables: Enable -annotate arg on early Unicodes

On early Unicode releases, there is no NChar property, and on V1.1.5, no
surrogates.  The code for -annotate previously assumed these existed,
so failed.  This moves the surrogates testing later, after new code that
specially handles the situation in 1.1.5, and has special handling for
the non-character code points, in that they may not exist in the current
version.