Bake Template: make fileextension configurable

[fabian-mcfly]

Currently, the php-Extension for newly baked templates is hardcoded. Thus it's not possible to create other filetypes without overwriting the whole TemplateCommand::bake method.

https://github.com/cakephp/bake/blob/1c8a2d7b6a15f4bbc77bf15c5c780fbceb41de35/src/Command/TemplateCommand.php#L359

[othercorey]

What other extensions would you use?

[fabian-mcfly]

Twig for example.

[othercorey]

This will be configurable with TemplateCommand::$ext in 2.8.