Add namespace translations for [ami] Amis and [pwn] Paiwan
Add namespace translations for these two languages.
Also add namespace aliases for straight apostrophe (') to
typographical apostrophe (’), so that links will still work
if someone uses the wrong one by mistake. This is also done
for [tay] Atayal language.
Also harmonizing fallback languages to be the same as for
other Taiwanese aboriginal languages (i.e. 'zh-tw, zh-hant,
zh-hans').
Bug: T292414
Bug: T292415
Change-Id: I755a0672ad05588d3e4352ea74d8c4854d9571a4