Added suspended audit state

New audit state SUSPENDED is added in this patch set. If audit
state with continuous mode is changed from ONGOING to SUSPENDED,
audit's job is removed and the audit is not executed.
If audit state changed from SUSPENDED to ONGOING in reverse,
audit is executed again periodically.

Change-Id: I32257f56a40c0352a7c24f3fb80ad95ec28dc614
Implements: blueprint suspended-audit-state

watcher/api/controllers/v1/utils.py

@@ -79,6 +79,15 @@ def get_patch_value(patch, key):
             return p['value']
 
 
+def check_audit_state_transition(patch, initial):
+    is_transition_valid = True
+    state_value = get_patch_value(patch, "state")
+    if state_value is not None:
+        is_transition_valid = objects.audit.AuditStateTransitionManager(
+            ).check_transition(initial, state_value)
+    return is_transition_valid
+
+
 def as_filters_dict(**filters):
     filters_dict = {}
     for filter_name, filter_value in filters.items():