mjjohnson

Implemented a TODO related to a token's counter. The counter is [stored by the token, starts at 0](http://fidoalliance.org/specs/fido-u2f-v1.0-ps-20141009/fido-u2f-implementation-considerations-ps-20141009.html#token-counters), and should always increase. If not, it [may be an indication that...

Right now all of the data files in a repository go into a single directory (`data/`). Given an average chunk size of 1MB, a 10TB repository would mean 10 million...