Allow var lookup plugin to operate on a list of terms

Not sure this has a good use case but it's how nearly all other lookups
work so we should support the common interface.

lib/ansible/plugins/lookup/var.py

@@ -63,8 +63,6 @@ from ansible.plugins.lookup import LookupBase
 class LookupModule(LookupBase):
 
     def run(self, terms, variables=None, **kwargs):
-
-        ret = []
         if variables is not None:
             self._templar.set_available_variables(variables)
         myvars = getattr(self._templar, '_available_variables', {})
@@ -72,14 +70,8 @@ class LookupModule(LookupBase):
         self.set_options(direct=kwargs)
         default = self.get_option('default')
 
-        # Assumes listify_plugin_terms is called previous to run so each term is already templated and terms is always a list
-        if isinstance(terms, list):
-            term = terms[0]
-        elif isinstance(terms, string_types):
-            term = terms
-        else:
-            raise AnsibleError('Invalid terms passed to "var" lookup, "%s" is not a string, its a %s' % (terms, type(terms)))
-
+        ret = []
+        for term in terms:
             if not isinstance(term, string_types):
                 raise AnsibleError('Invalid setting identifier, "%s" is not a string, its a %s' % (term, type(term)))
 
@@ -91,10 +83,11 @@ class LookupModule(LookupBase):
                     value = myvars['hostvars'][term]
                 else:
                     raise AnsibleUndefinedVariable('No variable found with this name: %s' % term)
-            ret = [self._templar.template(value, fail_on_undefined=True)]
+                ret.append(self._templar.template(value, fail_on_undefined=True))
+
             except AnsibleUndefinedVariable:
                 if default is not None:
-                ret = [default]
+                    ret.append(default)
                 else:
                     raise