Fix extension definition

[aledeg]

Before, extension was missing the definition of mandatory methods.
At the moment, it's not a problem because the coding guidelines are not
enforced by the code. But in the future, it will break.
Now, extension have all mandatory method definitions.

[kevinpapst]

BTW. there is an abstract(?) extension - these changes are completely unnecessary.
Wasted time for many developers (you and me here and all the others involved everywhere else) without ANY benefit.
These methods should have been introduced in the extensions base class.

[aledeg]

Those methods are mandatory but it's not enforced by the code. There is a discrepancy between what is required and what is done. That's why I've done that. This way, if it's mandatory, extensions need to define it.
This way, there is no magic behind how the extension works. Everything is defined in the extension and not in the Minz class.

You can add your view point to that PR because it's not yet merged. Discussion welcomed.

[kevinpapst]

I did, becuase my comment sounds harsh and I wanted to add some context

[aledeg]

Thank you for your concern. It's appreciated