Update gene-product-association-data-gpad-format.md

[suzialeksander]

updating existing doc from gpad1.1 _-> gpad 1.2.

I did NOT yet make changes to the body of this doc, based on https://github.com/geneontology/go-annotation/blob/master/specs/gpad-gpi-1_2.md

[suzialeksander]

hey @kltm is there anything else that should be mentioned for gpad 1.2 (possibility: add that .gpa OR .gpad are valid extensions- is this a change from GPAD 1.1?)

[kltm]

@suzialeksander I can't think of much else.
While I prefer "gpad" to "gpa", I think that might be personal and it is not defined in the spec?

[pgaudet]

GOA uses gpa as an extension

http://ftp.ebi.ac.uk/pub/databases/GO/goa/UNIPROT/
@alexsign

I dont know when/whether the file extension name was discussed; it would be good to harmonize across all groups.

Thanks, Pascale

[alexsign]

@pgaudet I cannot really answer this because decision to post GPAD files as gpa was made before I started at EBI.

[pgaudet]

Thanks @alexsign