VWR-22759 : port of SNOW-667, Automatic language translation of chat messages

doc/contributions.txt

indra/cmake/FindJsonCpp.cmake

indra/cmake/JsonCpp.cmake

indra/newview/CMakeLists.txt

indra/newview/app_settings/settings.xml

indra/newview/lltranslate.cpp

indra/newview/lltranslate.h

indra/newview/llviewermessage.cpp

...a/newview/skins/default/xui/da/panel_preferences_chat.xml

...a/newview/skins/default/xui/de/panel_preferences_chat.xml

indra/newview/skins/default/xui/en/floater_nearby_chat.xml

...a/newview/skins/default/xui/en/panel_preferences_chat.xml

...a/newview/skins/default/xui/es/panel_preferences_chat.xml

...a/newview/skins/default/xui/fr/panel_preferences_chat.xml

...a/newview/skins/default/xui/it/panel_preferences_chat.xml

...a/newview/skins/default/xui/ja/panel_preferences_chat.xml

...a/newview/skins/default/xui/pl/panel_preferences_chat.xml

...a/newview/skins/default/xui/pt/panel_preferences_chat.xml

install.xml