chore(lint): require semicolons

Relying on ASI (automatic semicolon insertion)
is allowed in TypeScript because JavaScript allows
it. However, when we run clang-format it doesn’t
understand that these statements are terminated
with a newline and changes the indentation, in bad
cases even breaking the code.

Fixes #817

modules/angular2/src/util/decorators.ts

@@ -70,7 +70,7 @@ export interface ParameterDecorator {
   /**
    * Invoke as ES7 decorator.
    */
-  (cls: Type, unusedKey: any, index: number): void
+  (cls: Type, unusedKey: any, index: number): void;
 }
 
 function extractAnnotation(annotation: any): any {