CCB 2021-05-05 review item.  Makes filenames better match terms
used in implementation.

The status code from the low level implementation needs to
be returned from the caller, in case it was not OS_SUCCESS.

Update most of the conditions in the "unit tests" to use the
support macros whenever possible.  The macros display the
function being called as well as the return value being checked
for, and therefore this makes it so the test log file can be
cross referenced back to the documentation to ensure the
documented return codes are being tested.

As a nice side effect this also removes quite a bit of
repetition in the test programs.

If messages (e.g. from UtPrintf, etc) already have a newline,
do not add another.

Fix #983, rename hooks to handlers

Fix #999, propagate status code in OS_rmdir

Fix #1002, remove extra newlines in utassert logs

Fix #981, rework "unit-tests" to use macros

This cuts the number of logged test cases from nearly 80k to about 580.

* Minor documentation enhancements

Fix #982, Add test for object id inline functions

Fix #994, fixed invalid inputs for OS_mkdir

Fix #986, Show CodeQL Preview

Update Readme and version.h