move all plugin tests out of babel-core and into their appropriate folders

packages/babel-plugin-transform-es2015-function-name/test/fixtures/function-name/modules-4/actual.js

@@ -0,0 +1,9 @@
+export function foo(bar) {
+
+}
+
+var bar = {
+  foo: function () {
+    foo;
+  }
+};

packages/babel-plugin-transform-es2015-function-name/test/fixtures/function-name/modules-4/expected.js

@@ -0,0 +1,8 @@
+export { _foo as foo };
+function _foo(bar) {}
+
+var bar = {
+  foo: function foo() {
+    _foo;
+  }
+};