Reimplement storage under a simpler namespace and load on 'loaded'

The loading of data on brain 'connected' was leading to a race were
brain data wasn't always being loaded at the right time.

Removes the unnecessary in-memory @cache (since most brain
implementations are already in-memory)
Merge pull request #14 from kiratalent/fix-persistence

Reimplement storage under a simpler namespace and load on 'loaded'