Add HTTP and REST gw addresses

[roman-khimov]

Is your feature request related to a problem? Please describe.

I'm always frustrated when people can't find GW addresses.

Describe the solution you'd like

Put them onto the page. Add a disclaimer that these are public gateways that MUST NOT be used for production applications, they're a centralization point and they're not guaranteed to always be available. But they can be used for test purposes. Name them "Test gateways".

[mike-petrov]

Do you mean https://rest.t5.fs.neo.org/v1 and https://http.t5.fs.neo.org? We should add it for both pages: testnet and mainnet?

[roman-khimov]

Yeah, we have them both for T5 and mainnet.