Implement horizontal scrolling

[AMythicDev]

This PR introduces horizontal scrolling into minus.

Roadmap

• [x] Introduce new public function to control line wrapping in Pager struct and Event variant related to it
• [x] New key bindings for moving left and right and new variant of UserInput to get events of horizontal scroll keys.
• [ ] Format text for wrapping only when line_wrapping is true in formatted_line function.

The entire roadmap is currently unclear, but I will make sure to update stuff where as we get closer to a working implementation.

Closes #59