Implement event manager class

On handling of property change event, If callback is
of type event then event manager would be asked to create
the event dbus objects.

Change-Id: I7f1d365d7f44a1cca54516e9ef555bb132d6b063
Signed-off-by: Ratan Gupta <ratagupt@in.ibm.com>
diff --git a/src/Makefile.am b/src/Makefile.am
index cf91619..94f81b8 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -10,7 +10,8 @@
 	elog.cpp \
 	main.cpp \
 	propertywatch.cpp \
-	resolve_errors.cpp
+	resolve_errors.cpp \
+	event_manager.cpp
 phosphor_dbus_monitor_LDADD = \
 	$(SDBUSPLUS_LIBS) \
 	$(PHOSPHOR_DBUS_INTERFACES_LIBS) \