feat/launcher icon

[seamuslowry]

Adding in monochrome icon support.

To create the mono icon, I

1. used the existing jerboa.xml as the launcher icon
2. removed all paths but the eye and the outline
3. removed fill from the outline and gave stroke the fill color
4. added a strokewidth so it would be visible

With fix:

Current compared against icon that does support it:

This also goes ahead and deletes all the default android icons that were still living in the mipmap folder.

As well, it'll have the side effect of using the jerboa icon for the placeholder loading image rather than the android icon (since it is using ic_launcher_foreground which is now the jerboa icon where it was the default android one

[kuro-codes]

I really like it too!