Add various options to verify ssl/tls client cert including letting the
application handle the authentication.
diff --git a/grpc.gemspec b/grpc.gemspec
index 9c858b2..bac1f18 100755
--- a/grpc.gemspec
+++ b/grpc.gemspec
@@ -171,6 +171,7 @@
s.files += %w( include/grpc/impl/codegen/sync_win32.h )
s.files += %w( include/grpc/impl/codegen/time.h )
s.files += %w( include/grpc/grpc_security.h )
+ s.files += %w( include/grpc/grpc_security_constants.h )
s.files += %w( include/grpc/census.h )
s.files += %w( src/core/lib/channel/channel_args.h )
s.files += %w( src/core/lib/channel/channel_stack.h )