Remove application owner role

[guidanoli]

📚 Context

Currently, each application can have an owner.
This owner is capable of changing the app's consensus at any time.
This power requires users to trust the app owner not to be malicious.
If #414 is implemented, this role will be obsolete.
This would allow us to remove the application owner role.
With #410, this would also allow us to remove IOwnable.

✔️ Solution

• Remove inheritance from Ownable to Application
• Remove inheritance from IOwnable to IApplication
• Remove initialOwner from Application constructor and factory