Fallback to Spanish rather than Portuguese

Proposed at phabricator:T150540. Any opinions?

(gl) Concordo coa proposta como proponente da mesma. Creo que aínda que existen similitudes entre o portugués e o galego, pensar que ambas as linguas poden ser intercambiables resulta incorrecto tanto no gramatical como no ortográfico. Resulta ademais lóxico pensar, creo eu, que ante unha mensaxe de interface sen traducir os usuarios enténdano antes en castelán que en portugués, pois o castelán é cooficial en Galicia, non así o portugués. Grazas.

Sorry, I didn't noticed that coment because I didn't watch pages at this wiki.

It could be good to fallback messages to spanish because all people at Galicia knows spanish, but in the other hand, in my work here at translatewiki, I have found that there are more messages translated to portuguese than to spanish, and with a greater quality. For this reason, I think that it could be more useful for galician users keep the fallback to portuguese. Bye.

Even though the average galician wikipedian has some kind of portuguese knowledge, mainly due to language proximity and similarities, spanish as failback makes a bit more sense for geographical and knowledge reasons. If it only affects MediaWiki it probably doesn't matter much either way, we got it mostly translated by now. I'm ok with the change, but it's probably a low priority task.