Add meta.type to rules

[stroncium]

• Added meta.type to rules
• Added test to check if fixable rules got types
• Updated new-rule.md

Fixes #202

[stroncium]

@sindresorhus Oh, by the way, I've made quite a lot of pull requests, but I still plan to do at least some minor refactoring after functionality is verified. I also plan to finish the remaining tasks from issuehunt. I've looked around the code and it seems the style goes left and right in every single piece of code. So, is there some official guidelines/request regarding that?

I myself prefer to write compact code with minimal comments, though some complex parts might get hard to understand from a glance(we're talking AST manipulations here after all), but if needed I can tweak the style the way maintainer(s?) seem fitting.

[sindresorhus]

I've looked around the code and it seems the style goes left and right in every single piece of code. So, is there some official guidelines/request regarding that?

Not exactly sure what you mean. Can you link to some examples of what you're referring to? "Official guidelines" for what exactly?

[stroncium]

Not exactly sure what you mean. Can you link to some examples of what you're referring to? "Official guidelines" for what exactly?

Comment density, code illustrative side(in a sense of being a good guide for new coming contributors), idiomatic vs readable vs expressive vs fast code, levels of DRY. But it's ok if there is no premade answers to those questions, a couple of reviews will be enough.