Updating pt-PT translation

[xbecas]

Contributing to #1138.

[tmontes]

Welcome @xbecas !... You can count on our assistance. :)

[tmontes]

@xbecas,

Per our conversation, here's what you need to continue your work here:

$ git checkout master
$ git fetch upstream
$ git merge master
$ git checkout update-pt-translate
$ git merge master

...update your translation now, then:

$ git add ...
$ git commit ...
$ git push mine update-pt-translate

This updates your GitHub update-pt-translate branch, which is tracked by this PR. :)

[tmontes]

Apart from a few message strings we're not sure how to translate -- no experience with ChromeOS / ChromeBooks -- we're pretty happy with this take.

Ready for merging! :)

[carlosperate]

Restarted the CI tests as it was hitting this issue: #1454
Should be good after the restart.

[carlosperate]

This is good to go, so let's merge it 🎉
Thanks @xbecas and @tmontes !