Revert "Implements check if item is already present"

This reverts commit d79101645df6026cdbe48b07307fe101413a7729.
Revert "Adds test"

This reverts commit b311fe3f8dab10a6c8811dcc2204b7c156d8b537.
Revert "Adds new test data"

This reverts commit 997070656fc003f824aefa3f3f2840dd39c8318f.
Makes days map a global lookup table
Makes rss replace channels and items, thus making it stateless
Makes atom replace channels and items, thus making it stateless
Removes notification of new channels

This is going to be moved to the stateful Feed, this is yet to be
implemented.
Removes new Item notification
Fixes the tests

Reference the item directly through channel as the notification
functionality has been removed.
Adds a database.

This is a really simple map. Calls to it just check if the key exists
and return a bool. In case of a false it adds the key.
The key is just a string which might or might not be sufficient.
Adds the database for checking new channels/items.

In this iteration the key passed to the database is the Title which is
obviously silly.
I'm still looking for a configurable way of generating the unique key.
Adds Key()
Adds a fallback ID function.
Add check if the handler exists.
Revert "Revert "Adds new test data""

This reverts commit 79d418e00a22c053393cb4536e457d6e36494202.
Adds test for the new items