Refactor ingestion

This refactor of the code makes it so that

1) ingest.js merely depends on urls/file paths in order to get data
2) jellyfish has a pluggable intermediate storage implementation that allows for swapping out storage parameters
3) Fixes usage of hakken and initialization of server

I have verified that this works locally with carelink and dexcom.  Both currently suffer from a bug in sandcastle that causes it to only store 64K of data.  dexcom also apparently suffers from a bug in the parser that causes it to fail.  But, it appears to be properly handing off.