screenshot frames for project pages

[jodygarnett]

The graphic designer we hired showed project page mockups using laptops, tablets, browsers window to frame project screen shots.

Sadly we only got a template for the laptop frame.

This pull-request includes a vector design using sketch for the missing frames. I used a paint program to make the screen area transparent so it should be "easy" to use this to frame a screen snap in a simple graphic program.

While this is a best-effort result I would prefer if we hire the graphic designer again.

Before

After

[jodygarnett]

You do not have commit access, perhaps we can fix that.

[astroidex]

yes please.