Axios ES2017 (#4787)

* Added AxiosHeaders class;

* Fixed README.md href;

* Fixed a potential bug with headers normalization;

* Fixed a potential bug with headers normalization;
Refactored accessor building routine;
Refactored default transforms;
Removed `normalizeHeaderName` helper;

* Added `Content-Length` accessor;
Added missed `has` accessor to TS types;

* Added `AxiosTransformStream` class;
Added progress capturing ability for node.js environment;
Added `maxRate` option to limit the data rate in node.js environment;
Refactored event handled by `onUploadProgress` && `onDownloadProgress` listeners in browser environment;
Added progress & data rate tests for the http adapter;
Added response stream aborting test;
Added a manual progress capture test for the browser;
Updated TS types;
Added TS tests;
Refactored request abort logic for the http adapter;
Added ability to abort the response stream;

* Remove `stream/promises` & `timers/promises` modules usage in tests;

* Use `abortcontroller-polyfill`;

* Fixed AxiosTransformStream dead-lock in legacy node versions;
Fixed CancelError emitting in streams;

* Reworked AxiosTransformStream internal logic to optimize memory consumption;
Added throwing an error if the request stream was silently destroying (without error) Refers to #3966;

* Treat the destruction of the request stream as a cancellation of the request;
Fixed tests;

* Emit `progress` event in the next tick;

* Initial refactoring;

* Refactored Mocha tests to use ESM;

* Refactored Karma tests to use rollup preprocessor & ESM;
Replaced grunt with gulp;
Improved dev scripts;
Added Babel for rollup build;

* Added default commonjs package export for Node build;
Added automatic contributors list generator for package.json;

Co-authored-by: Jay <jasonsaayman@gmail.com>

test/specs/defaults.spec.js

@@ -1,8 +1,9 @@
-var defaults = require('../../lib/defaults');
-var utils = require('../../lib/utils');
+import defaults from '../../lib/defaults';
+import utils from '../../lib/utils';
+import AxiosHeaders from '../../lib/core/AxiosHeaders';
 
 describe('defaults', function () {
-  var XSRF_COOKIE_NAME = 'CUSTOM-XSRF-TOKEN';
+  const XSRF_COOKIE_NAME = 'CUSTOM-XSRF-TOKEN';
 
   beforeEach(function () {
     jasmine.Ajax.install();
@@ -17,13 +18,13 @@ describe('defaults', function () {
   });
 
   it('should transform request json', function () {
-    expect(defaults.transformRequest[0]({foo: 'bar'})).toEqual('{"foo":"bar"}');
+    expect(defaults.transformRequest[0]({foo: 'bar'}, new AxiosHeaders())).toEqual('{"foo":"bar"}');
   });
 
   it("should also transform request json when 'Content-Type' is 'application/json'", function () {
-    var headers = {
+    const headers = new AxiosHeaders({
       'Content-Type': 'application/json',
-    };
+    });
     expect(defaults.transformRequest[0](JSON.stringify({ foo: 'bar' }), headers)).toEqual('{"foo":"bar"}');
     expect(defaults.transformRequest[0]([42, 43], headers)).toEqual('[42,43]');
     expect(defaults.transformRequest[0]('foo', headers)).toEqual('"foo"');
@@ -34,23 +35,23 @@ describe('defaults', function () {
   });
 
   it("should transform the plain data object to a FormData instance 'Content-Type' if header is 'multipart/form-data'", function() {
-    var headers = {
+    const headers = new AxiosHeaders({
       'Content-Type': 'multipart/form-data'
-    };
+    });
 
-    var payload = {x: 1};
+    const payload = {x: 1};
 
-    var transformed = defaults.transformRequest[0](payload, headers);
+    const transformed = defaults.transformRequest[0](payload, headers);
 
     expect(transformed).toEqual(jasmine.any(FormData));
   });
 
   it('should do nothing to request string', function () {
-    expect(defaults.transformRequest[0]('foo=bar')).toEqual('foo=bar');
+    expect(defaults.transformRequest[0]('foo=bar', new AxiosHeaders())).toEqual('foo=bar');
   });
 
   it('should transform response json', function () {
-    var data = defaults.transformResponse[0].call(defaults, '{"foo":"bar"}');
+    const data = defaults.transformResponse[0].call(defaults, '{"foo":"bar"}');
 
     expect(typeof data).toEqual('object');
     expect(data.foo).toEqual('bar');
@@ -92,7 +93,7 @@ describe('defaults', function () {
   });
 
   it('should use default config for custom instance', function (done) {
-    var instance = axios.create({
+    const instance = axios.create({
       xsrfCookieName: XSRF_COOKIE_NAME,
       xsrfHeaderName: 'X-CUSTOM-XSRF-TOKEN'
     });
@@ -127,7 +128,7 @@ describe('defaults', function () {
   });
 
   it('should use header config', function (done) {
-    var instance = axios.create({
+    const instance = axios.create({
       headers: {
         common: {
           'X-COMMON-HEADER': 'commonHeaderValue'
@@ -163,7 +164,7 @@ describe('defaults', function () {
 
   it('should be used by custom instance if set before instance created', function (done) {
     axios.defaults.baseURL = 'http://example.org/';
-    var instance = axios.create();
+    const instance = axios.create();
 
     instance.get('/foo');
 
@@ -174,7 +175,7 @@ describe('defaults', function () {
   });
 
   it('should not be used by custom instance if set after instance created', function (done) {
-    var instance = axios.create();
+    const instance = axios.create();
     axios.defaults.baseURL = 'http://example.org/';
 
     instance.get('/foo');