Added data URL support for node.js; (#4725)

* Added data URL support for node.js;
Added missed data URL protocol for the browser environment;
Optimized JSON parsing in the default response transformer;
Refactored project structure;
Added `cause` prop for AxiosError instance that refers to the original error if it was wrapped with `AxiosError.from` method;
Added fromDataURI helper;
Added test for handling data:url as an `arraybuffer|text|stream`;

* Added throwing of 405 HTTP error if the method is not GET;

lib/core/AxiosError.js

@@ -64,7 +64,9 @@ var descriptors = {};
   'ERR_DEPRECATED',
   'ERR_BAD_RESPONSE',
   'ERR_BAD_REQUEST',
-  'ERR_CANCELED'
+  'ERR_CANCELED',
+  'ERR_NOT_SUPPORT',
+  'ERR_INVALID_URL'
 // eslint-disable-next-line func-names
 ].forEach(function(code) {
   descriptors[code] = {value: code};
@@ -83,6 +85,8 @@ AxiosError.from = function(error, code, config, request, response, customProps)
 
   AxiosError.call(axiosError, error.message, code, config, request, response);
 
+  axiosError.cause = error;
+
   axiosError.name = error.name;
 
   customProps && Object.assign(axiosError, customProps);