When the mean is 0, the coefficient of variation is calculated to be
NaN, which is not meaningful, so instead of printing "+-NaN%", just
don't print the CV at all.
Closes#908Closes#1444
Add two factory static functions to Injector: resolveAndCreate and
fromResolvedBindings.
We want to avoid resolution and flattening every time we create a new
injector. This commit allows the user to cache resolved bindings and
reuse them.