refactor: simplify and make tests work in JS and Dart

* remove `wraps` syntax enhancements for imports
  and support new `import * as module from ...` syntax

  - default imports are the wrong construct for importing
    everything from a module

* moved tests from transpiler to jasmine and karma

  - transpiler tests are included when running karma in main project folder
  - transpiler is reloaded after every test run in karma,
    so no need to restart karma when the transpiler has been changed.
  - removed own gulp build for transpiler and `postinstall.sh`
    as they are no more needed.
  - transpiler tests are now executed in Dart AND JavaScript (used to be executed
    only in Dart), which allowed to catch some bugs (see the bug with the
    import specification above).

* made tests work in dart as well by using the following hack:

  - dependencies are loaded from the `build` folder, which makes
    running `gulp build` necessary before running karma for dart
  - for this to work,
    the dependencies are included in main `pubspec.yaml` of project
  - reason for the hack: `karma-dart` loads all `packages` urls
    directly from disc (should rather use the karma file list)

* added explicit annotations `FIELD`, `ABSTRACT`, ... to `facade/lang.*`

  - needed for now that we can run tests and don't get errors for undefined
    annotations.

* added `README.md` with details about the build and tests

modules/core/src/annotations/directive.js

@@ -1,5 +1,7 @@
 import {Type} from 'facade/lang';
 import {ElementServicesFunction} from './facade';
+import {ABSTRACT} from 'facade/lang';
+
 
 @ABSTRACT
 export class Directive {

modules/core/src/compiler/compiler.js

@@ -2,6 +2,7 @@ import {Future, Type} from 'facade/lang';
 import {Element} from 'facade/dom';
 import {ProtoView} from './view';
 import {TemplateLoader} from './template_loader';
+import {FIELD} from 'facade/lang';
 
 export class Compiler {
 

modules/core/src/compiler/element_injector.js

@@ -1,4 +1,4 @@
-
+import {FIELD} from 'facade/lang';
 
 /**
 

modules/core/src/compiler/view.js

@@ -1,10 +1,12 @@
 import {DOM, Node, DocumentFragment, TemplateElement} from 'facade/dom';
-import {ListWrapper wraps List} from 'facade/collection';
+import {ListWrapper} from 'facade/collection';
 import {ProtoWatchGroup, WatchGroup, WatchGroupDispatcher} from 'change_detection/watch_group';
 import {Record} from 'change_detection/record';
 import {Module} from 'di/di';
 import {ProtoElementInjector, ElementInjector} from './element_injector';
 import {SetterFn} from 'change_detection/facade';
+import {FIELD, IMPLEMENTS} from 'facade/lang';
+import {List} from 'facade/collection';
 
 @IMPLEMENTS(WatchGroupDispatcher)
 export class View {

modules/core/src/life_cycle/life_cycle.js

@@ -1,9 +1,11 @@
+import {FIELD} from 'facade/lang';
+
 export class LifeCycle {
-  
+
   @FIELD('final _changeDetection:ChangeDetection')
   @FIELD('final _onChangeDispatcher:OnChangeDispatcher')
   constructor() {}
-  
+
   digest() {
     _changeDetection.detectChanges();
     _onChangeDispatcher.done();