split roles bin lib

[plebhash]

close #820

as stated in #702, it is desirable to have some clear distinction between:

• reference implementation for roles (bin)
• reusable high-level APIs for roles implementations (lib)

so we should split the roles workspace in two distinct directories, one for lib (APIs) and one for bin (executable applications).

a *_bin suffix was added to the name of binary crates (to avoid name clash), which now have the following names:

• jd_client_sv2_bin (also added _sv2 for consistency with other roles)
• jd_server_sv2_bin (also added _sv2 for consistency with other roles)
• proxy_sv2_bin (removed mining_ from the beginning to avoid redundancy)
• pool_sv2_bin
• translator_proxy_sv2_bin (added _proxy to make it clear this is another kind of proxy)

library crates now have the following names:

• jd_client_sv2 (added _sv2 for consistency with other roles)
• jd_server_sv2 (added _sv2 for consistency with other roles)
• proxy_sv2 (removed mining_ from the beginning to avoid redundancy)
• network_helpers_sv2
• pool_sv2
• rpc_sv2
• translator_proxy_sv2 (added _proxy to make it clear this is another kind of proxy)

config-examples only exist for binary crates
main.rs and args.rs only exist for binary crates
lib.rs (+ all other internal logic) only exist for library crates

[lorbax]

Is this PR supposed to be against main?

[plebhash]

Is this PR supposed to be against main?

no, just fixed for dev