The format of /healthz is not consistent across components

[matthewdarwin]

The format of /healthz is not consistent across components. For example:

eosws:

{"errors":[],"hub":{"head_block_num":146217680,"head_block_time":"2020-10-09T14:30:44.5Z","time_latency_sec":0},"healthy":{"hub":true}}

statedb:

ready

eosq:

ok

Of course it is reasonable that different components have different amounts of information to share, but the format should be consistent. (eg always json with status true/false)