Add new translations from Transifex.

New languages:

et - Estonian
ca - Catalan
fo - Faroese
fr_CA - French (Canada)
hr_HR - Croatian (Croatia)
km - Khmer
ms_MY - Malay (Malaysia)
pt_BR - Portuguese (Brazil)
ro - Romanian
si_LK - Sinhala (Sri Lanka)
sk_SK - Slovak (Slovakia)
sl_SI - Slovenian (Slovenia)
sr - Serbian
th - Thai
uk - Ukrainian
zh_TW - Chinese (Taiwan)