Rework urlAbsolute to be a little more streamlined.

Rework urlAbsolute to be a little more streamlined.

The primary aim of this is to cut down on the number of ways snprintf was
called in the original version.  The idea here is to build the common base
portion of the url using snprintf and then construct the rest using str[n]cpy.
snprintf is still used as the alternative (using only POSIX routines) involves
a much longer run of code that, at least in my estimation, gains us very little
over snprintf.