Simplify scaffolded Ignite App to the bare minimum

[jeronimoalbi]

Ignite Apps can be scaffolded using ignite app scaffold but the resulting code have comments and examples that in most of the cases would end up being removed. This can be seen in the example app.

Scaffolding a minimum app should be the default. Ignite Apps are not complex and can be learned by reading the official Ignite documentation on how to write Apps.

The current efforts on having a repo with different basic examples of Ignite Apps also makes scaffolding extra code and comments unnecessary.

It would also be entirely possible to add simple comments to the scaffolded apps where a link to the examples repository could be added.