Eliminate alphanet mentions
Clarification and motivation
Problem: we still have many mentions of
alphanet.sh in code despite it is not even part of the repository and it is apparently outdated now.
For instance, see tests on Michelson serialization.
alphanet.shmentions are replaced with
tezos-client, except for cases when we want to describe our old experiments.
- Our documentation describes how to get
tezos-clientexecutable (probably putting a link to our tezos-packaging repo should be enough).