web form upload demo: golang
Merge pull request #1 from xushiwei/master

web form upload demo: golang
mv PutPolicy to github.com/qiniu/api
Merge pull request #2 from xushiwei/master

mv PutPolicy to github.com/qiniu/api
uploadWithKey
Merge pull request #3 from xushiwei/master

uploadWithKey
for golang sdk: v5.0.0
support custom field - x:
Merge pull request #4 from xushiwei/master

for golang sdk: v5.0.0
CHANGLOG v5.0.0
Merge pull request #6 from xushiwei/master

CHANGLOG v5.0.0
Update CHANGELOG.md
Update CHANGELOG.md
Merge pull request #5 from qiniu/develop

Release v5.0.0