Return camel-case codes

[freenerd]

In develop the body of successful responses returns "code": "ok" but to stay in line with the documentation this should be camel-case "code": "Ok"

[freenerd]

Looks like codes generally aren't camel cased at the moment, e.g.

{ code: 'no-route', message: 'Impossible route between points' }

[emiltin]

it might be a matter of style, but i prefer lowercase 'ok' and 'no-route'

[freenerd]

@emiltin there is definitely no right or wrong answer here. the only weak argument i have is that 5 days ago we already discussed this and the new docs have camel case now.

[TheMarex]

Done.