Eliminated some clumsiness in instrumentation code.

When a flag is initialized true, set false by some failure-handling
code and then conditioned on, it can be eliminated in favour of just
having an else to the failure-handler.  Arithmetic with doubles really
doesn't need to cast anything like so much to doubles; anything
multiplied by an overt double (e.g. 1e3) is implicitly converted to
double anyway.
Make IsMatchItemIn()'s list const-compatible.

IsMatchItemIn() doesn't modify the list, so don't claim it does !
Prefer memrchr() over strrchr().

Jimis pointed out in code-review that I could have done this, and
it'll save strrchr()'s search for the '\0' byte whose location I
already know.  Depends on memrchr(), a GNU extension, but Jimis
assures me we have a replacement for it in our emulation layer.
Use the test-frameworks's assertions, not <assert.h>'s assert()

In the unit test system use the right assert mechanisms for the
purpose in hand.  Also renamed a macro: it asserts that the system is
initialized; it doesn't "assert if the system is initialized" because
"assert" doesn't mean "fail an assertion" !
Merge pull request #1447 from ediosyncratic/tidy-ups

Tidy ups