Introduce additional config for TypeScript

[kirill-konshin]

In addition to config portion for React (https://github.com/benmosher/eslint-plugin-import/blob/master/config/react.js) I suggest to create a portion for TypeScript in a separate file:

{
  "settings": {
    "import/resolver": {
      "node": {
        "extensions": [
          ".js",
          ".jsx",
          ".ts",
          ".tsx"
        ]
      }
    }
}

In this case instead of endless copy-paste of this section users would simply add something like plugin:import/typescript to their configs.

[kirill-konshin]

Pull created #1257.

[ACVis]

Forgive my ignorance, but I don't see any documentation on this. Would we use this, by adding the following in our .eslintrc.js?

module.exports = {
    extends: [
        "plugin:import/typescript",
    ]
}

In which case, solely adding that would be enough configuration for the typescript use case?
Also, I know vaguely, that this is how shareable configs work, I just don't see any mentions of these incredibly useful configs in the readme/docs, even though they exist in the repository.

[kirill-konshin]

PR created #1277