Change Bake templates to be view based

This is a little rough around the edges, but aught to be good enough to now discuss.

The main functional benefit introduced here is that php tags in a bake template are treated as plain text. I.e. whereas before a template looked like this:

    echo "<?php\n"; ?>
    namespace <?= $namespace ?>\Controller\Component;

Now, by using a different tag pair to indicate template logic, it would look like this:

    <?php
    namespace <%= $namespace %>\Controller\Component;

I haven't fully converted the existing [template templates](https://github.com/AD7six/cakephp/tree/3.0-bake-view/src/Template/Bake/Template), apart from just cleaning them up there's the opportunity to move any of the ugly logic into a helper/element to simplify things (either in this PR or at any point in the future).
Maybe this sort of thing would be less saddness:

```
class View {

    public function __construct($options = []) {
        foreach(['request', 'response', 'eventManager'] as $obj) {
            if (isset($options[$obj])) {
                $this->$obj($options[$obj]);
            }
        }
    }

    public function request($request = null) {
        if ($request) {
            return $this->request = $request;
        }
        if (!$this->request) {
            $this->request = new Request();
        }
        return $this->request;
    }

    // etc.
}