Add new changelog design

[mojganii]

This PR provides new face for changelog view. In addition, It makes it accessible through Settings view.

Before	After

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This change is 

[linear]

IOS-988 Add a changelog view

[buggmagnet]

Reviewed 17 of 17 files at r1, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @mojganii)

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ios/MullvadVPN/Views/MainButton.swift line 11 at r1 (raw file):

import SwiftUI
enum ImagePosition {
    case leading

nit
This feels quite a generic name for something that's only used by the MainButton
I think we should rename it MainButtonImagePosition, or maybe move that enum down in the MainButton struct instead.