Remove wallet from CLI

[quentinlesceller]

Simply remove the wallet command and argument not used since grin v1.1.0

[quentinlesceller]

Random macOS failure (CI only):

running 1 test
2020-06-10T17:13:31.088316+00:00 INFO grin_util::logger - log4rs is initialized, stdout level: Debug, min. level: Debug
2020-06-10T17:13:31.089873+00:00 DEBUG grin_store::lmdb - DB Mapsize for .grin/peer is 1048576
2020-06-10T17:13:32.148293+00:00 DEBUG grin_p2p::peer - connect: handshaking with Ok(V4(127.0.0.1:49394))
2020-06-10T17:13:32.193398+00:00 DEBUG grin_p2p::peer - accept: handshaking from Ok(V4(127.0.0.1:49395))
2020-06-10T17:13:32.193636+00:00 DEBUG grin_p2p::handshake - Connected! Cumulative 3 offered from PeerAddr(V4(127.0.0.1:49394)), ProtocolVersion(2), "MW/Grin 4.0.0-beta.1", UNKNOWN
2020-06-10T17:13:32.193735+00:00 DEBUG grin_p2p::peers - Saving newly connected peer 127.0.0.1:5000.
2020-06-10T17:13:32.193790+00:00 DEBUG grin_p2p::store - save_peer: PeerAddr(V4(127.0.0.1:5000)) marked Healthy
thread 'peer_read' panicked at 'GLOBAL_CHAIN_TYPE and CHAIN_TYPE unset. Consider set_local_chain_type() in tests.', core/src/global.rs:172:17
stack backtrace:
error: test failed, to rerun pass '-p grin_p2p --test peer_handshake'

[antiochp]

👍