Add additional debugging info for ceph write times

So we can differentiate lock contention vs. slow writes.
Rates are more useful than straight timestamps
Fix scope issues
Some things were made to be pointy
Minor bump
Clean up nomenclature a bit
Gah, that's not how division works
Infix is apparently clearer than prefix
Merge branch 'master' into more-debugging

Conflicts:
	vaultaire.cabal
Merge pull request #59 from anchor/more-debugging

Add additional debugging info for ceph write times
Merge branch 'master' of https://github.com/anchor/vaultaire into telemetry

Conflicts:
	lib/Vaultaire/Writer.hs