[#51] Change App name and favicon

closes #51 (closed)

I added different title depending on the page the user is

By order:

1. When pages are loading
2. Channels list page
3. Specific channel page (Notifications page)
4. Specific channel page (Preferences page)
5. Preferences page
6. Devices page
7. Channel management page

If you want another text or format just tell me 😄