Added stub for write label.
Added stub for write label.

Omegaice/smartcontainers,crcresearch/smartcontainers,cwilli34/smartcontainers,dahuo2013/smartcontainers,cwilli34/smartcontainers,charlesvardeman/smartcontainers,crcresearch/smartcontainers,dahuo2013/smartcontainers,cwilli34/smartcontainers,crcresearch/smartcontainers,dahuo2013/smartcontainers,Omegaice/smartcontainers,Omegaice/smartcontainers