Cleanup and refactoring of parseResultLine logic.

With two sets of mutually similar if-statements in caller-side and
callee-side logic, I decided to collapse the whole shebang and use
object polymorphism to eliminate much of the control flow confusion.

The end result is:

1) Easier to expand in the future if need be, and,
2) Easier for someone fluent in OO to understand what's happening.