C TAP Harness 2.3

This release pushes out some improvements to my TAP library and test harness that I found time to do a while back. I have some other plans, but not much time, so I'm not sure when I'll get to them.

Now included in the C TAP library is a test_cleanup_register function that registers a cleanup function called during exit from the test. This function will be passed a boolean argument indicating whether the test succeeded or failed. It was already possible to do this with simple atexit, but now callers can decide whether to delete possibly-interesting trace files based on whether the test was successful.

As part of this change, I also refactored and improved everything that happens during test exit, and in the process fixed a bug where lazy plans and test summaries were still displayed even when a test aborted with bail.

This release also adds the gcc warn_unused_result attribute to the various TAP library functions (mostly the malloc variations that call bail on failure) where the return value really shouldn't be ignored.

You can get the latest release from the C TAP Harness distribution page.