Chapter 9 / 18 - add failing test by specifying expected outcome

Notes:
1. Another failing test isn't resolved yet.
2. The old stress test still fails / crashes when the
test executable is run repeatedly in an endless loop.
Chapter 9 / 19 - fix new test

Note: There is still something fundamentally wrong with the old stress test.
Chapter 9 / 20..21 - refactor locationIsUnknown()

Note: The old stress test still fails / crashes when the
test executable is run repeatedly in an endless loop.
Chapter 9 / 22 - eliminate helper; it's no longer needed.

Note: The old stress test still fails / crashes when the
test executable is run repeatedly in an endless loop.
Chapter 9 / 23 - example for a slow-to-read (hard-to-understand) test.

Note: The old stress test still fails / crashes when the
test executable is run repeatedly in an endless loop.
Chapter 9 / 24 - additional performance test

Note: The old stress test still fails / crashes when the
test executable is run repeatedly in an endless loop.
Chapter 9 / 25 - additional test now with *20

Note: The old stress test now hangs.
Chapter 9 / 26 - small refactoring

Note: The old stress still appears to hang.
Chapter 9 / 27 - undo some of previous changes, refactor

Note: The old stress still appears to hang.
Chapter 9 / 28

Notes:
The old stress test still fails.
Chapter 9 / 28 - remove this (again)

Notes:
The old stress test still fails.
Attempt to get Mac OS configuration right
Deal with -Werror,-Wunused-private-field
Further adjustments for Mac OS

e.g. use target configs rather than separate projects
Fix Mac OS Yosemite problem

initially only for C7.
Chapter 7 / 18 - fix unused parameters.
Chapter 7 / 18 - use CHECK_THROWS() macro.
Ignore *.app.
Separate post build steps for Mac / PC
Chapter 9 / 28 - sanitize for Mac OS X

Notes:
The old stress test still fails.