Sketch of race mode.
Merge branch 'master' into race
Tests for race mode.
Loosen encoding to handle any 4xx errors.
Add tests for dead memcached client.
Simplify source get logic.
Smarter handling of non-encoded errors.
Add note in README about modes.
Merge branch 'master' into race
Less diff.
Typo.
Merge pull request #9 from mapbox/race

Race mode