More quality quality

[Daniel van Vugt]

All,

I'd like (in the somewhat distant future) for us to be able to run Mir's 
tests under helgrind [1] so that we can automatically detect races in 
continuous integration.

It's not going to be a short journey, as there's a fair amount of errors 
to fix yet. They're mostly benign but the noise easily hides real bugs. 
So in the mean time, if you write any new code that crosses multiple 
threads, please try to run your individual test cases under helgrind and 
check no new races are being introduced.

[1] valgrind --tool=helgrind

- Daniel