DeprecationWarning: passlib.utils.generate_password
DeprecationWarning: passlib.utils.generate_password

After looking at the periodic py27 job with oslo master I found a
deprecation warning that states the following:

trove/common/utils.py:290: DeprecationWarning: the function
passlib.utils.generate_password() is deprecated as of Passlib 1.7,
and will be removed in Passlib 2.0, use passlib.pwd.genword() /
passlib.pwd.genphrase() instead.

I simply replaced the function call and arguments with genword.

Change-Id: Id3cc81678ff856b8a11ea96242b958fa0e5cef87

zhangg/trove,openstack/trove,zhangg/trove,hplustree/trove,hplustree/trove,openstack/trove