templateAdapter: avoid dynamic require if possible

I thought I'd experiment with packaging Rendr under webpack. I've got around most issues with some method overriding but this one remains and a monkey-patch for it seems to be very heavy-handed. I believe the patch is clean enough to not break backwards compatibility. Note `templateAdapterModule` is now the module itself rather than its name.

(In my code I'm overriding methods like `ModelUtils::fetchConstructor`, `Router::getRouteBuilder`, `Router::getAction`, and `BaseView.getView` to do requires from my code rather than from Rendr's context.)