Add blob/master/

* Add the small capital letters dead key

It can be added to the keyboard from the settings or into custom layouts
as `accent_small_caps`.

Add all the symbols listed on https://en.wikipedia.org/wiki/Small_caps

This allows assigning mappings to letters without changing the Shift
mappings and making uppercase impossible to type.

For gestures, the Shift modifier is still applied first, unless a custom
mapping for <fn/> is set for the key.

* Add <row scale=""> attribute

Scale the width of the keys in the row to match a value. Useful to
remove space on the right of the row without adding a 'width' attribute
to each key.

* layouts: Use the 'scale=""' attribute in builtin layouts

This removes the very specific 'width' values.

The non-backward-compatible change to the XML should be mentioned as users must revise their layouts.