refactor(pipes): use Injector instead of pipe factories for pipe instantiation

BREAKING CHANGE
    - Pipe factories have been removed.
    - PIpe names to pipe implementations are 1-to-1  instead of 1-to-*

 Before:
     class DateFormatter {
         transform(date, args){}
     }

     class DateFormatterFactory {
       supporst(obj) { return true; }
       create(cdRef) { return new DateFormatter(); }
     }
     new Pipes({date: [new DateFormatterFactory()]})

After
    class DateFormatter {
      transform(date, args){}
    }
    new Pipes({date: DateFormatter})

modules/angular2/src/transform/template_compiler/change_detector_codegen.dart

@@ -274,10 +274,7 @@ class _CodegenState {
 
     var read = '''
       if ($_IDENTICAL_CHECK_FN($pipe, $_UTIL.uninitialized)) {
-        $pipe = ${_names.getPipesAccessorName()}.get('$pipeType', $context, $cdRef);
-      } else if (!$pipe.supports($context)) {
-        $pipe.onDestroy();
-        $pipe = ${_names.getPipesAccessorName()}.get('$pipeType', $context, $cdRef);
+        $pipe = ${_names.getPipesAccessorName()}.get('$pipeType', $cdRef);
       }
       $newValue = $pipe.transform($context, [$argString]);
     ''';