Add symbol packages

[pakrym]

@davidfowl @anurse

[dnfclas]

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[analogrelay]

Conflicts! :(.

Looks good though, if the conflicts don't change it dramatically.

[davidfowl]

This doesn't look complete. Where are the source files being added? Make sure this works end to end

[davidfowl]

Also make sure it does the same thing as dnu pack

[pakrym]

That's embarrassing, somehow I was sure symbols package was only for symbols. Would fix and double test.

[pakrym]

🆙 📅

[davidfowl]

Looks good.