Merge pull request #4580 from jboeuf/cpp_auth_doc

Fixing cpp auth doc pointers.

include/grpc++/client_context.h

@@ -244,7 +244,7 @@ class ClientContext {
   /// client’s identity, role, or whether it is authorized to make a particular
   /// call.
   ///
-  /// \see  https://github.com/grpc/grpc/blob/master/doc/grpc-auth-support.md
+  /// \see  http://www.grpc.io/docs/guides/auth.html
   void set_credentials(const std::shared_ptr<CallCredentials>& creds) {
     creds_ = creds;
   }

include/grpc++/security/credentials.h

@@ -55,7 +55,7 @@ class SecureCallCredentials;
 /// It can make various assertions, e.g., about the client’s identity, role
 /// for all the calls on that channel.
 ///
-/// \see https://github.com/grpc/grpc/blob/master/doc/grpc-auth-support.md
+/// \see http://www.grpc.io/docs/guides/auth.html
 class ChannelCredentials : public GrpcLibrary {
  public:
   ~ChannelCredentials() GRPC_OVERRIDE;
@@ -80,7 +80,7 @@ class ChannelCredentials : public GrpcLibrary {
 /// A call credentials object encapsulates the state needed by a client to
 /// authenticate with a server for a given call on a channel.
 ///
-/// \see https://github.com/grpc/grpc/blob/master/doc/grpc-auth-support.md
+/// \see http://www.grpc.io/docs/guides/auth.html
 class CallCredentials : public GrpcLibrary {
  public:
   ~CallCredentials() GRPC_OVERRIDE;