Unify coreAliasing, externalRuntime and externalRegenerator

Merge all three transformers into the `selfContained` transformer,
as discussed in Gitter.  Name may not be final.

test/fixtures/transformation/optional-core-aliasing/es6-destructuring/actual.js

@@ -1 +0,0 @@
-var [a, [b], [c], d] = ["hello", [", ", "junk"], ["world"]];

test/fixtures/transformation/optional-core-aliasing/es6-destructuring/expected.js

@@ -1,30 +0,0 @@
-"use strict";
-
-var _slicedToArray = function (arr, i) {
-  if (Array.isArray(arr)) {
-    return arr;
-  } else {
-    var _arr = [];
-
-    for (var _iterator = _core.$for.getIterator(arr), _step; !(_step = _iterator.next()).done;) {
-      _arr.push(_step.value);
-
-      if (i && _arr.length === i) break;
-    }
-
-    return _arr;
-  }
-};
-
-var _core = require("6to5-runtime/core-js");
-
-var _ref = ["hello", [", ", "junk"], ["world"]];
-
-var a = _ref[0];
-var _ref$1 = _slicedToArray(_ref[1], 1);
-
-var b = _ref$1[0];
-var _ref$2 = _slicedToArray(_ref[2], 1);
-
-var c = _ref$2[0];
-var d = _ref[3];

test/fixtures/transformation/optional-core-aliasing/es6-spread/actual.js

@@ -1 +0,0 @@
-var lyrics = ["head", "and", "toes", ...parts];

test/fixtures/transformation/optional-core-aliasing/es6-spread/expected.js

@@ -1,9 +0,0 @@
-"use strict";
-
-var _toArray = function (arr) {
-  return Array.isArray(arr) ? arr : _core.Array.from(arr);
-};
-
-var _core = require("6to5-runtime/core-js");
-
-var lyrics = ["head", "and", "toes"].concat(_toArray(parts));

test/fixtures/transformation/optional-core-aliasing/options.json

@@ -1,4 +0,0 @@
-{
-  "optional": ["coreAliasing"],
-  "experimental": true
-}

test/fixtures/transformation/optional-external-regenerator-runtime/options.json

@@ -1,3 +0,0 @@
-{
-  "optional": ["externalRegenerator"]
-}

test/fixtures/transformation/optional-external-runtime/amd/expected.js

@@ -1,6 +0,0 @@
-define(["exports", "6to5-runtime/6to5", "someModule"], function (exports, _to5Runtime6to5, _someModule) {
-  "use strict";
-
-  var _to5Runtime = _to5Runtime6to5;
-  var foo = _to5Runtime.interopRequire(_someModule);
-});

test/fixtures/transformation/optional-external-runtime/options.json

@@ -1,3 +0,0 @@
-{
-  "optional": ["externalRuntime"]
-}

test/fixtures/transformation/optional-self-contained/aliased-constructors/expected.js

@@ -1,7 +1,11 @@
 "use strict";
 
+var _to5Runtime = require("6to5-runtime/6to5");
+
 var _core = require("6to5-runtime/core-js");
 
+var _regeneratorRuntime = require("6to5-runtime/regenerator");
+
 obj.constructor === Object;
 obj.constructor === _core.Promise;
 

test/fixtures/transformation/optional-self-contained/es6-for-of/expected.js

@@ -1,7 +1,11 @@
 "use strict";
 
+var _to5Runtime = require("6to5-runtime/6to5");
+
 var _core = require("6to5-runtime/core-js");
 
+var _regeneratorRuntime = require("6to5-runtime/regenerator");
+
 for (var _iterator = _core.$for.getIterator(arr), _step; !(_step = _iterator.next()).done;) {
   var i = _step.value;
 }

test/fixtures/transformation/optional-self-contained/es7-array-comprehensions/expected.js

@@ -1,7 +1,11 @@
 "use strict";
 
+var _to5Runtime = require("6to5-runtime/6to5");
+
 var _core = require("6to5-runtime/core-js");
 
+var _regeneratorRuntime = require("6to5-runtime/regenerator");
+
 var arr = (function () {
   var _arr = [];
 

test/fixtures/transformation/optional-self-contained/options.json

@@ -0,0 +1,4 @@
+{
+  "optional": ["selfContained"],
+  "experimental": true
+}

test/fixtures/transformation/optional-self-contained/regenerator-runtime/expected.js

@@ -1,5 +1,9 @@
 "use strict";
 
+var _to5Runtime = require("6to5-runtime/6to5");
+
+var _core = require("6to5-runtime/core-js");
+
 var _regeneratorRuntime = require("6to5-runtime/regenerator");
 
 void _regeneratorRuntime.mark(function callee$0$0() {

test/fixtures/transformation/optional-self-contained/runtime-amd/expected.js

@@ -0,0 +1,8 @@
+define(["exports", "6to5-runtime/6to5", "6to5-runtime/core-js", "6to5-runtime/regenerator", "someModule"], function (exports, _to5Runtime6to5, _to5RuntimeCoreJs, _to5RuntimeRegenerator, _someModule) {
+  "use strict";
+
+  var _to5Runtime = _to5Runtime6to5;
+  var _core = _to5RuntimeCoreJs;
+  var _regeneratorRuntime = _to5RuntimeRegenerator;
+  var foo = _to5Runtime.interopRequire(_someModule);
+});

test/fixtures/transformation/optional-self-contained/runtime-commonjs/expected.js

@@ -2,4 +2,8 @@
 
 var _to5Runtime = require("6to5-runtime/6to5");
 
+var _core = require("6to5-runtime/core-js");
+
+var _regeneratorRuntime = require("6to5-runtime/regenerator");
+
 var foo = _to5Runtime.interopRequireWildcard(require("someModule"));