Allow "Back" swiping gesture on Mac

[OskarEichler]

Preflight Checklist

• I have read the Contributing Guidelines for this project.
• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Problem Description

On Mac you can do a two finger swipe on the trackpad to go back. This is common behavior when browsing on Chrome. It would be great if Ferdium allows this as well, so that when using Gitlab for example and navigating to some other pages it is easy to return to the previous page, since there are no actual back buttons.

Proposed Solution

Allow "Back" Gesture via Trackpad.

Alternatives Considered

Don't really think that there should be a back button, so I think gesture based would be good

Additional Information

No response