README.md

Note that the live version of the SSTL Design Document can be found here:

https://docs.google.com/document/d/1wNUKeTsitHc6M3Hf8fiF9PxTNUS0z07V-TF2fHk_Cl0/edit#heading=h.qc30e2dhfuvy

The test plan can be found here:

https://docs.google.com/document/d/10iLDM0b94K7rww_zCMV8WxE8dIj6Qx67KeUhLqMiLy0/edit