**breaking change**: Switch Face and related classes to v2::KeyChain

security::v2::KeyChain is now exposed as ndn::KeyChain, which should
ensure that dependent code can be mostly compiled.  However, expect code
that explicitly uses the old KeyChain interface to be broken.

Change-Id: I7330d0250d92f3f0f2570ab6d0214ab3dfdd18cc
Refs: #3098
diff --git a/src/util/dummy-client-face.cpp b/src/util/dummy-client-face.cpp
index af1f702..79586c6 100644
--- a/src/util/dummy-client-face.cpp
+++ b/src/util/dummy-client-face.cpp
@@ -86,13 +86,13 @@
 
 DummyClientFace::DummyClientFace(const Options& options/* = DummyClientFace::DEFAULT_OPTIONS*/)
   : Face(make_shared<DummyClientFace::Transport>())
-  , m_internalKeyChain(new security::v1::KeyChain)
+  , m_internalKeyChain(new KeyChain)
   , m_keyChain(*m_internalKeyChain)
 {
   this->construct(options);
 }
 
-DummyClientFace::DummyClientFace(security::v1::KeyChain& keyChain,
+DummyClientFace::DummyClientFace(KeyChain& keyChain,
                                  const Options& options/* = DummyClientFace::DEFAULT_OPTIONS*/)
   : Face(make_shared<DummyClientFace::Transport>(), keyChain)
   , m_keyChain(keyChain)
@@ -103,13 +103,13 @@
 DummyClientFace::DummyClientFace(boost::asio::io_service& ioService,
                                  const Options& options/* = DummyClientFace::DEFAULT_OPTIONS*/)
   : Face(make_shared<DummyClientFace::Transport>(), ioService)
-  , m_internalKeyChain(new security::v1::KeyChain)
+  , m_internalKeyChain(new KeyChain)
   , m_keyChain(*m_internalKeyChain)
 {
   this->construct(options);
 }
 
-DummyClientFace::DummyClientFace(boost::asio::io_service& ioService, security::v1::KeyChain& keyChain,
+DummyClientFace::DummyClientFace(boost::asio::io_service& ioService, KeyChain& keyChain,
                                  const Options& options/* = DummyClientFace::DEFAULT_OPTIONS*/)
   : Face(make_shared<DummyClientFace::Transport>(), ioService, keyChain)
   , m_keyChain(keyChain)