Improve coverage test for "shared" layer #230
Description
This is a follow-on to original ticket #28
As part of the original change sets, a basic coverage test was added for the shared layer. It calls most functions in a nominal case, but does not yet cover a sufficient number of the error cases. For instance the module loader only has 72% of line coverage. Others are between 80-90% but could still be improved (files, queues, timers).
It has been discussed in CCB meetings during the review for #28 that we should make another pass through the coverage test logs to improve the error case coverage prior to releasing the next OSAL.