.tx/config: Use language mappings for android "tx pull"

The language names we are using in the android resources differ from those on Transifex.

We need to manually specify mappings for them, so Transifex is able to place the files in the correct folders.

dist/languages/.tx/config

@@ -11,3 +11,4 @@ type = QT
 file_filter = ../../src/android/app/src/main/res/values-<lang>/strings.xml
 source_file = ../../src/android/app/src/main/res/values/strings.xml
 type = ANDROID
+lang_map = ja_JP:ja, ko_KR:ko, pt_BR:pt-rBR, pt_PT:pt-rPT, ru_RU:ru, vi_VN:vi, zh_CN:zh-rCN, zh_TW:zh-rTW