blink(1) sconces

I think the metal frame-based mounting is working well.

Also this...

I think frame-mounted sconces work better.

The first attempt (uploaded as "blink1SconceFrameArch1.stl") is much more stable than the PCB-based mounts.

Problems with this first attempt though:

* mounting arms block some of the side-emitting light

* mounting grippers are 2mm too wide on each side

Thus fixes to try:

* move mounting arms forward towards USB jack: gives more space for light

* eliminate 2mm space on grippers

There are two methods I can see for attaching add-on diffusers to blink(1):

* mount directly to PCBA

* mount to metal frame (that carries PCBA)

I was initially designing for the former, but I think it will be structurally stronger (and safer for the PCBA) if I design for the latter.

I've uploaded several attempts at PCBA-mounted sconces. They work... sorta.

Things I like about some of the designs, even with the bad mounting technique:

* the circular arc diffuser is minimally classic

* two of the designs have inserts for a message to help define what the blink(1) is for (see the "NO NO NO") in one of the photos