Use more C++17 features

Mainly structured bindings, inline variables, and class template
argument deduction, plus many more smaller things.

Change-Id: I810d17e0adb470426e4e30c898e03b3140ad052f
diff --git a/daemon/table/cs-policy.cpp b/daemon/table/cs-policy.cpp
index b51aac1..6b24eb3 100644
--- a/daemon/table/cs-policy.cpp
+++ b/daemon/table/cs-policy.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2019,  Regents of the University of California,
+ * Copyright (c) 2014-2022,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -59,7 +59,7 @@
   return policyNames;
 }
 
-Policy::Policy(const std::string& policyName)
+Policy::Policy(std::string_view policyName)
   : m_policyName(policyName)
 {
 }