Add wiki

[chibicitiberiu]

While we are trying to build an application that is intuitive and easy to use, some things require a more in-depth explanation.

It would be best to build a wiki that covers all these topics.

So far, these are the topics I thought about:

• installation (standalone, docker) - I know this is covered in the readme's, we can move some of the information to keep it all in one place
• configuration (i.e. using the config.ini file)
• importing subscriptions (from YT or text file)