This commit starts from the simple premise that the use of node settings
in blob store repositories is a mistake. Here we see that the node
settings are used to get default settings for store and restore throttle
rates. Yet, since there are not any node settings registered to this
effect, there can never be a default setting to fall back to there, and
so we always end up falling back to the default rate. Since this was the
only use of node settings in blob store repository, we move them. From
this, several places fall out where we were chaining settings through
only to get them to the blob store repository, so we clean these up as
well. That leaves us with the changeset in this commit.
3d64605075