Fix line break
Merge pull request #303 from thockin/docs

Fix line break
pkg/registry now passed race detector.
use mutex instead of rwmutex
Merge pull request #306 from monnand/registry-race

Solved data races in pkg/registry
Break the dep from util -> api

Part 1 in a series of changes towards data validation.
Merge pull request #308 from thockin/valid2

Break the dep from util -> api
Add a FileServer for master's logs