Hierarchical sigma formulation does not work with improper priors for
all the sigmas; the posterior appears to be improper (I haven't proved
it, but this is quite likely), with an unbounded peak in density at zero
for all but two of the sigmas. The initRun() now checks for a global
sigma flag before allowing an improper HyperbolicPrior to be used,
otherwise an InverseGamma(0.001,0.001) is used.
Removed reference to unversioned file that was there for test purposes.