core: global io_service and scheduler

Scheduler and time are imported from ndn-cpp-dev.
Forwarder is using the new scheduler API.
Face system is not transitioned yet.

refs #1290

Change-Id: I5679cb50bbf9890a105f663b038f13951403c2b6
diff --git a/daemon/table/measurements.hpp b/daemon/table/measurements.hpp
index 0fa24e0..4c6d946 100644
--- a/daemon/table/measurements.hpp
+++ b/daemon/table/measurements.hpp
@@ -20,8 +20,7 @@
 class Measurements : noncopyable
 {
 public:
-  explicit
-  Measurements(boost::asio::io_service& ioService);
+  Measurements();
 
   ~Measurements();
 
@@ -71,7 +70,6 @@
 private:
   std::map<Name, shared_ptr<measurements::Entry> > m_table;
 
-  Scheduler m_scheduler;
   static const time::Duration s_defaultLifetime;
 };