prop249: advertise support correctly in protover subsystem; only use when protover support advertised
In the link handshake and in the protover list, we should advertise support for CREATE2V and CREATED2V.
In the protover list, we should advertise support for fragmented EXTEND cells.
In the protover list, we should advertise support for our temporary testing handshake.
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information