Add SAM DA1 family

[jordiorlando]

Add Microchip SAM DA1 family (everything except the chip-scale packages). Aliases of SAM D21 family from #2336, see screenshots/discussion from there.

Datasheet

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All contributions to the kicad library must follow the KiCad library convention

Thanks for creating a pull request to contribute to the KiCad libraries! To speed up integration of your PR, please check the following items:

• Provide a URL to a datasheet for the symbol(s) you are contributing
• An example screenshot image is very helpful
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  • A new fitting footprint must be submitted if the library does not yet contain one.
• If there are matching footprint PRs, provide link(s) as appropriate
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[cpresser]

Hi and sorry for the huge delay.

I see you did add new symbols and not just aliases. That I don't understand (yet).
For example it seems to me that ATSAMDA1J14B-A and ATSAMD21J15A-A are identical and could use the alias feature.

[jordiorlando]

@cpresser good question, I don't remember why I decided to do that. I think just aliases should be fine. I'll try to change that now.

[jordiorlando]

@cpresser changed to be aliases

[cpresser]

Looks good. Thanks!