Add timer class support

Watchdog implementation uses sd_event_timer at the backend and this
commit has that timer backend support.

Change-Id: Ib6dbd5d6bb617c20d7361e0852a916aa506d5aad
Signed-off-by: Vishwanatha Subbanna <vishwa@linux.vnet.ibm.com>
diff --git a/Makefile.am b/Makefile.am
index 370d024..888f8cf 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,5 +1,13 @@
 sbin_PROGRAMS = phosphor-watchdog
 
+noinst_HEADERS = timer.hpp
+
 phosphor_watchdog_SOURCES = \
-				argument.cpp \
-				mainapp.cpp
+                argument.cpp \
+                timer.cpp \
+                mainapp.cpp
+
+phosphor_watchdog_LDFLAGS = $(SYSTEMD_LIBS) \
+                            ${PHOSPHOR_LOGGING_LIBS}
+phosphor_watchdog_CXXFLAGS = $(SYSTEMD_CFLAGS)\
+                             ${PHOSPHOR_LOGGING_CFLAGS}