Persist changes to settings

Persist changes made to settings, if any, such that those changes can be
restored upon a reboot.

Use Cereal for serialization of the settings' properties. Since the
settings code is generated based on a system specific settings policy,
generate the serialization code as well such that only relevant settings
are serialized.

Resolves openbmc/openbmc#1764.

Change-Id: Id8bd84a9455cf4348b22f255d038b050d004eb7c
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>
diff --git a/Makefile.am b/Makefile.am
index 65f95cb..55ea2d6 100755
--- a/Makefile.am
+++ b/Makefile.am
@@ -30,4 +30,5 @@
 
 phosphor_settings_manager_LDADD = \
 	$(PHOSPHOR_DBUS_INTERFACES_LIBS) \
-	$(SDBUSPLUS_LIBS)
+	$(SDBUSPLUS_LIBS) \
+	-lstdc++fs