Use osc-lib instead of openstackclient

osc-lib is a package of common support modules for writing
OSC plugins. All common functions, classes such as exceptions,
utils, logs and so on have been moved from openstackclient to
osc-lib.

So use osc-lib instead of openstackclient.

Change-Id: I8041ad5c9ff9b3c0ff772e632f401c638bb293b5

mistralclient/osc/plugin.py

@@ -13,7 +13,7 @@
 
 import logging
 
-from openstackclient.common import utils
+from osc_lib import utils
 
 LOG = logging.getLogger(__name__)
 

requirements.txt

@@ -2,10 +2,10 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 cliff!=1.16.0,!=1.17.0,>=1.15.0 # Apache-2.0
+osc-lib>=0.1.0 # Apache-2.0
 osprofiler>=1.3.0 # Apache-2.0
 pbr>=1.6 # Apache-2.0
 python-keystoneclient!=1.8.0,!=2.1.0,>=1.7.0 # Apache-2.0
-python-openstackclient>=2.1.0 # Apache-2.0
 PyYAML>=3.1.0 # MIT
 requests>=2.10.0 # Apache-2.0
 six>=1.9.0 # MIT

test-requirements.txt

@@ -3,6 +3,7 @@
 # process, which may cause wedges in the gate later.
 hacking<0.11,>=0.10
 pylint==1.4.5 # GPLv2
+python-openstackclient>=2.1.0 # Apache-2.0
 sphinx!=1.3b1,<1.3,>=1.2.1 # BSD
 unittest2 # BSD
 fixtures>=3.0.0 # Apache-2.0/BSD