Set title and favicon of monitor pages

**Is your feature request related to a problem? Please describe.**
All statuspages have the (html-)title "Peekaping" and the peekaping favicon. When dealing with multiple status pages in different tabs it's hard to find the right page/tab.

**Describe the solution you'd like**
Let the users choose an individual (html-)title and favicon per status page.

**Describe alternatives you've considered**
Alternatively use the status' page name as html title. (Favicon could be part of global settings,)

Look for the HTML template files that render the status page header, likely in a templates or web directory. The title and favicon are set there. Check if there's a configuration model for a status page to add title and favicon URL fields. Verify the change by running the app and viewing a status page's tab.

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