Duplicates in output trust list

[YuryStrozhevsky]

After I run command

node src/bin/tl-create.js --apple --mozilla --eutl --microsoft --format pkijs roots.pkijs

I have too many duplicates in the list. Better would be to filter already existing certificates during making final output.

[fotisl]

Duplicate entries allow a user to differentiate the properties of a certificate at each trust store. For example, a CA Certificate may be EV enabled for one trust store and not EV enabled for another. Merging these two entries would remove this information.