Update DevTools icons

[nt1m]

@fvsch updated the devtools icons to match the photon design. It would be nice to include them here.

[fvsch]

I was waiting to finish the Debugger icon updates before making a PR here, but we can probably do it in two batches.

[nt1m]

@fvsch Is this something you have time to do ? :)

[ariasuni]

Any news on this?