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/http/backends/xhr_backend.ts

@@ -42,7 +42,7 @@ export class XHRConnection implements Connection {
         responseOptions = baseResponseOptions.merge(responseOptions);
       }
 
-      ObservableWrapper.callNext(this.response, new Response(responseOptions))
+      ObservableWrapper.callNext(this.response, new Response(responseOptions));
     });
     // TODO(jeffbcross): make this more dynamic based on body type