More control over image placement on elements.

[MyreMylar]

Is your feature request related to a problem? Please describe.
Right now when you stick an image on a button it is always centred. It'd be more useful if we could control them like we can the text, possibly have more options like stretching the image to fit the element.

Describe the solution you'd like

• Ability to align images to the left or right, top or bottom as well as the centre in the theme.
• Stretch to fit option, ignores placement and resizes the image to fit the drawable shape inside the
  shadow and border

Additional context
Hopefully this would make it easy to do things like have file and folder icons in the file dialog next to their names indicating which was which.

[MyreMylar]

See also #145