Implement Report persistency

Now Report properties are stored in non-volatile memory. It allows
to restore Report after system restart. Persistency of a report is
controlled by Persistency property in Report interface.

Tested:
 - Passed unit tests
 - Verified that report is stored in /var/lib/telemetry dir
 - Verified that report is restored from storage after telemetry
   service start

Signed-off-by: Wludzik, Jozef <jozef.wludzik@intel.com>
Change-Id: Iccfe21603eecffc4e174a4403f699b03de320db9
diff --git a/tests/src/printers.hpp b/tests/src/printers.hpp
new file mode 100644
index 0000000..e187f35
--- /dev/null
+++ b/tests/src/printers.hpp
@@ -0,0 +1,3 @@
+#pragma once
+
+#include "printers/interfaces/json_storage.hpp"
\ No newline at end of file