Merge pull request #29 from qiniu/develop

Release v6.0.0 (patch 2)
Merge pull request #30 from qiniu/develop

Release v6.0.1
Merge pull request #31 from qiniu/develop

Release v6.0.2
Merge pull request #32 from qiniu/develop

Release v6.0.3
Merge pull request #33 from qiniu/develop

Release v6.0.4
sdkspec for language
resolve confliction
Merge pull request #34 from xushiwei/master

sdkspec for languages
Merge pull request #35 from qiniu/master

Master