security: Reorganizing source code to prepare for support of two version of NDN certificates

This commit also removes unused ndn_digestSha256 function and deprecates
crypto::sha256 in favor of crypto::computeSha256Digest in util/crypto.hpp.

Change-Id: I24ee50ff073a96b868633bdf2cfade412d3605f3
Refs: #3098
diff --git a/src/security/pib-sqlite3.hpp b/src/security/pib-sqlite3.hpp
index 7e867cd..f8665c5 100644
--- a/src/security/pib-sqlite3.hpp
+++ b/src/security/pib-sqlite3.hpp
@@ -92,12 +92,12 @@
   hasKey(const Name& identity, const name::Component& keyId) const final;
 
   virtual void
-  addKey(const Name& identity, const name::Component& keyId, const PublicKey& publicKey) final;
+  addKey(const Name& identity, const name::Component& keyId, const v1::PublicKey& publicKey) final;
 
   virtual void
   removeKey(const Name& identity, const name::Component& keyId) final;
 
-  virtual PublicKey
+  virtual v1::PublicKey
   getKeyBits(const Name& identity, const name::Component& keyId) const final;
 
   virtual std::set<name::Component>
@@ -115,12 +115,12 @@
   hasCertificate(const Name& certName) const final;
 
   virtual void
-  addCertificate(const IdentityCertificate& certificate) final;
+  addCertificate(const v1::IdentityCertificate& certificate) final;
 
   virtual void
   removeCertificate(const Name& certName) final;
 
-  virtual IdentityCertificate
+  virtual v1::IdentityCertificate
   getCertificate(const Name& certName) const final;
 
   virtual std::set<Name>
@@ -130,7 +130,7 @@
   setDefaultCertificateOfKey(const Name& identity, const name::Component& keyId,
                              const Name& certName) final;
 
-  virtual IdentityCertificate
+  virtual v1::IdentityCertificate
   getDefaultCertificateOfKey(const Name& identity, const name::Component& keyId) const final;
 
 private: