Load TSV into SQLite, including _meta columns and _conflict table

[jamesaoverton]

Building on #3 and jamesaoverton/cmi-pb-terminology#18, we need to load the TSV data into SQLite tables:

1. for subset tables, we need to leaving room to track validation errors and conflicts using _meta columns and _conflict tables
2. for full tables we just need to load the data as TEXT This can be handled by ontodev/sprocket#11.

For a given reference ID "1037960" we should create a build/ref:1037960/data.db file.