Move decl of Allocator::operator<< so it can be used in Allocator.
Move decl of Allocator::operator<< so it can be used in Allocator.

alexfrolov/grappa,alexfrolov/grappa,buaasun/grappa,uwsampa/grappa,buaasun/grappa,alexfrolov/grappa,buaasun/grappa,alexfrolov/grappa,buaasun/grappa,alexfrolov/grappa,uwsampa/grappa,buaasun/grappa,alexfrolov/grappa,uwsampa/grappa,uwsampa/grappa,alexfrolov/grappa,uwsampa/grappa,buaasun/grappa,buaasun/grappa,uwsampa/grappa,uwsampa/grappa