Merge branch 's3' of github.com:dt3310321/cos-python-sdk-v5 into s3

fix upload file from buffer

Author: dt3310321

qcloud_cos/version.py

@@ -1,2 +1,2 @@
 
-__version__ = '5.1.6.7'
+__version__ = '5.1.6.8'

setup.py

@@ -16,7 +16,7 @@ def long_description():
 
 setup(
     name='cos-python-sdk-v5',
-    version='1.6.7',
+    version='1.6.8',
     url='https://www.qcloud.com/',
     license='MIT',
     author='tiedu, lewzylu, channingliu',