security: Support ECDSA verification in all related classes.
This commit also addresses some old issues, such as "using namespace std".
Change-Id: I62b8ff97fb2b6f6cfe04b0ad5866bc0797e6e43b
Refs: #1660
diff --git a/src/security/sec-tpm.cpp b/src/security/sec-tpm.cpp
index 2011a95..3191095 100644
--- a/src/security/sec-tpm.cpp
+++ b/src/security/sec-tpm.cpp
@@ -27,10 +27,10 @@
#include "../encoding/buffer-stream.hpp"
#include "cryptopp.hpp"
-using namespace std;
-
namespace ndn {
+using std::string;
+
ConstBufferPtr
SecTpm::exportPrivateKeyPkcs5FromTpm(const Name& keyName, const string& passwordStr)
{