Quote devstack_localrc arguments

If you have

 devstack_localrc:
   ARGUMENT: "argument with spaces"

The quotes get lost during YAML processing and the resulting file has

  ARGUMENT=argument with spaces

which is a shell error.

Quote all arguments to avoid this sort of thing.

Change-Id: Ia63a53d745dfea7262bcdb5d46425f431c3ccfe5

Author: ianw

roles/write-devstack-local-conf/library/devstack_local_conf.py

@@ -252,7 +252,7 @@ def handle_localrc(self, localrc):
         if localrc:
             vg = VarGraph(localrc)
             for k, v in vg.getVars():
-                self.localrc.append('{}={}'.format(k, v))
+                self.localrc.append('{}="{}"'.format(k, v))
                 if k == 'LIBS_FROM_GIT':
                     lfg = True
                 elif k == 'TEMPEST_PLUGINS':

roles/write-devstack-local-conf/library/test.py

@@ -185,7 +185,7 @@ def test_overridelibs_from_git(self):
             for line in f:
                 if line.startswith('LIBS_FROM_GIT'):
                     lfg = line.strip().split('=')[1]
-        self.assertEqual('oslo.db', lfg)
+        self.assertEqual('"oslo.db"', lfg)
 
     def test_plugin_circular_deps(self):
         "Test that plugins with circular dependencies fail"
@@ -265,7 +265,7 @@ def test_tempest_plugins_not_overridden(self):
         lc.write(p['path'])
 
         tp = self._find_tempest_plugins_value(p['path'])
-        self.assertEqual('someplugin', tp)
+        self.assertEqual('"someplugin"', tp)
         self.assertEqual(len(lc.warnings), 1)