[New] order: Add support for TypeScript's "import equals"-expressions

[manuth]

This PR will add support for TypeScript's import =-syntax.

TypeScript not only allows you to import modules using import path = require("path"), but also to import entities for easier access:

import { Rule } from "eslint";
import RuleContext = Rule.RuleContext;

As the 2nd sort of import doesn't refer to a module, the name of this import will be set to null.
The sorting-functions for alphabetized imports has been updated according to this change.

Object-imports (which have their name set to null) will be forced to be put at the end of the group.

This PR fixes #1244

[coveralls]

Coverage increased (+0.003%) to 97.741% when pulling 62b554b on manuth:import-equals into 2e72af5 on benmosher:master.

[coveralls]

Coverage increased (+0.002%) to 97.74% when pulling 2c61a52 on manuth:import-equals into 3f46ccf on benmosher:master.

[coveralls]

Coverage increased (+0.002%) to 97.74% when pulling 2c61a52 on manuth:import-equals into 3f46ccf on benmosher:master.

[ljharb]

LGTM pending nits

[manuth]

Sorry - totally forgot to have a look at the code-formatting of this project 😅

[ljharb]

i think i messed up the syntax in my suggestions

[manuth]

@ljharb will a minor release be created automatically?

[ljharb]

No, I'll be cutting one after I clear through my current notification/PR backlog.

[manuth]

Awesome, thank you very much! 😄