Update Icons

Subdivided the new icons in 3 size categories. As requested by UX
Used the company naming scheme for uniformity and easy recognition.

Known issues:
- Top/Bottom category wasn't taken into account by UX at the time. Since
 this is a recent addition. Both the Walls and Top/Bottom will be updated.
- Cloud/Network connection icons 12px don't render correctly. Due to the
 theme-ing.
- Extruder Icons do not render correctly.

CURA-8010_new_icons

resources/qml/Account/AvatarImage.qml

@@ -52,7 +52,7 @@ Item
         width: parent.width + 2
         height: parent.height + 2
         visible: hasAvatar
-        source: UM.Theme.getIcon("circle_outline")
+        source: UM.Theme.getIcon("CircleOutline")
         sourceSize: Qt.size(parent.width, parent.height)
         color: UM.Theme.getColor("account_widget_outline_active")
     }