stage0: stream image to avoid extra copy
pkg/tarheader: vet fix

Fix the following vet report:
  - pkg/tarheader/pop_darwin.go:1: +build comment must appear before package clause and be followed by a blank line
Merge pull request #131 from ceh/vet-fix

pkg/tarheader: vet fix
Update SPEC.md

Removes duplicate 'the' in logging section.
Merge pull request #137 from lamielle/patch-1

appc/spec: fix typo
Merge pull request #129 from jonboulle/master

stage0: stream image to avoid extra copy
appc/spec: clarify authors annotation
Merge pull request #141 from jonboulle/master

App Manifest authors format: wrong example?
appc/spec: remove duplicated line
appc: remove unnecessary bracket in README
Merge pull request #152 from azu/patch-1

appc: remove unnecessary bracket in README