Drop support for older versions of the hidden service protocol
We've supported v3 introduce{1,2} cells since 0.2.1.
We've supported v2 descriptors since 0.2.0.
There is no need for clients and servers to continue supporting older versions of the hidden service protocols; there is probably no need for "hidden service authorities" to exist; and there is probably a bunch of other code here we can discard too.
The one wrinkle to think about is that removing support here might enable an adversary to tell when a client or service has switched to a newer version of Tor. Generally, we don't care about that, but we should still think about it.
To upload designs, you'll need to enable LFS and have admin enable hashed storage. More information