Draft: Interface_CAN_LIN: Add Isolated CAN transceivers from Analog, TI and Maxim

Sorry for the size of this merge request. I thought I could create a symbol shape that would work for many of the isolated CAN transceivers and in verifying that ended up defining symbols for several of them and thought it might be a useful contribution.

The symbol is the same size as used for several of the non-isolated transceivers such as the MCP2251 and has the RXD/TXD & CANH/CANL pins in the same location. I left space at the bottom left for common control functions like standby or silent in the same place as for the non-isolated devices even though these particular devices don't have that.

The isolators have SOIC-8 and SOIC-16 packages and on the large package the extra pins either stack to GND or are NC. On the Maxim devices the NC pins are left visible as the datasheet says they can be left unconnected or tied to ground. This KLC violation is intentional.

Also, for the ADM3050ExW ground pin 15 is visible rather than pin 9 because the layout recommended in the datasheet has the bypass capacitor located between 15 and 16 so I thought it made more sense to have 15 showing even though this is a KLC violation.

Datasheets in the symbols:

https://www.analog.com/media/en/technical-documentation/data-sheets/ADM3050E.pdf https://www.analog.com/media/en/technical-documentation/data-sheets/ADM3056E.pdf https://www.analog.com/media/en/technical-documentation/data-sheets/ADM3055E-3057E.pdf https://www.analog.com/media/en/technical-documentation/data-sheets/adm3058e.pdf https://www.ti.com/lit/gpn/iso1042 https://www.ti.com/lit/gpn/iso1044 https://datasheets.maximintegrated.com/en/ds/MAX14878-MAX14880.pdf

Symbols used in a schematic: Symbol_Editing.pdf

This references the RI-20-1 footprint from Analog, defined in PR: kicad-footprints!2726 (merged)