`display-name` `ignoreTranspilerName` is too strict

The purpose of ignoreTranspilerName is to ignore inferred names:

const SFC = () => <div />; // inferred name
const Foo = class extends React.Component {} // inferred name

It should not, however, ignore explicit names:

function SFC() { return <div />; } // explicit name
class Foo extends React.Component {} // explicit name

I think that the ignoreTranspilerName option should be deprecated, and replaced with new options that cover the current use cases:

1. always require an explicit displayName (ignoreTranspilerName: true)
2. only require an explicit displayName on React.createClasses (ignoreTranspilerName: false)

As well as cover these additional use cases:

1. always require an explicit name - ie, an explicit displayName or a named function or named `class
2. always require a name - either explicit, or ES6-inferred
3. Never allow an explicit displayName? (i don't really care about this one, but it seems useful for consistency)