Note: I have deleted commented code as per the suggestion of @utkarsh2102.
Note 2: I have fixed all the diffs, etc.

fixes #214

Limiting improves readability on wide monitors.

The immediate update of the settings is done by just exposing settings
as properties and then setting the settings as a context property.

Use Nico's suggestion to just leverage the width of the field, and leave
a comment.

don't use members format camelCaseTail_

to save on recalculation of the size and having to subtract the margins
to do the tally, then re-apply.

Removed empty labels in favour of a fixed height and bottom alignment.

use QString instead of std::string (QStringLiteral doesn't have a
constructor with int, str.)

remove temp variable, and just deal with it inline.

 - Switch to {} widget initialization
 - set fixed size on the Toggles so they don't scale down vertically
 - add another setting section for INTERFACE
 - add a placeholder value for deviceFingerprintValue_ so it can calculate the right size.
 - fix warnings about `QLayout: Attempting to add QLayout "" to UserSettingsPage "",` in boxWrap
 - hide widgets properly in Q_OS_MAC
 - remove mainLayout_ completely
 - clean up resizeEvent

This allows form fields to wrap dynamically when they are too long for
the view. This should help mobile and small screen users to configure
the app without having to force it into portrait mode, or not be able to
reach the settings fields at all.

markdown -> Markdown