Part Request: 4x4 Membrane switch Keyboard

Need a 4x4 membrane switch keyboard / membrane matrix with the following layout:

8 Female pins are used.

```
1 2 3 A
4 5 6 B
7 8 9 C
* 0 # D
```

The request is for a 4x4 membrane-switch keyboard part with eight female pins and the shown key layout. Start by reviewing existing parts in this repository for the expected Fritzing representation; done means the new part represents all 16 keys and exposes the requested eight pins.

Written by the indexing model from the issue text.