Implement "format" validation

[kylef]

• [ ] date-time
• [ ] email
• [ ] hostname
• [x] ipv4
• [x] ipv6
• [x] uri

[fruitcoder]

Hey kylef. Your library seems to be the only code that actually tries to validate Json on the client. All the other libraries are just decoding a Json into a model object. I would really love to here if you will work on this project or if you already have another solution. The formatting check is the most valuable for me.

[dydus0x14]

@fruitcoder this project is not already alone:) I suggest using Bender which supports validating and mapping at the same time. It is written in Swift, uses templates and extendable: you can add for checking any logic which you want.

[yspreen]

@dydus0x14 Bender isn't just a json scheme validator. It maps swift objects to json. It's not the same. I'll create a PR for this repo to support date

[yspreen]

Actually #118 looks really good. I think I'll use that branch for now

[yspreen]

Still had some issues, #121 should be good.