Merge pull request #31 from qiniu/develop

Release v6.0.0
Merge pull request #39 from qiniu/develop

for docs.qiniu.com release 6.1.2
Merge pull request #41 from qiniu/develop

Replace text picture with real picture
Merge pull request #45 from qiniu/develop

fix lost tag in put & add some sample to image process
Merge pull request #47 from qiniu/develop

Release 6.1.3
Merge pull request #51 from qiniu/develop

Release 6.1.4
add resumble
add resumble
add resumble
add resumble
resumble up
resumble up
resumble up
resumble up
resumble up
resumble up
resumble up
resumble up
resumble up
resumble up