Add option to enable "Do not Track" header

[BlobCodes]

Is your feature request related to a problem? Please describe.
The do not track option in most modern browsers shows websites a user does not want to be tracked, resulting in slightly better privacy. I'd like to use this feature, but sadly it is not included in wexond

Describe the solution you'd like
Implement a checkbox in the settings affecting both the DNT-header as well as the JavaScript function "navigator.doNotTrack" (both testable at https://browserleaks.com/donottrack)

Describe alternatives you've considered
None.

Additional context
None.