Internationalization

[benhylau]

Copy of: https://github.com/benhylau/flying-photo-booth/issues/30

Strings that need translation can be found here:

• https://github.com/groundupworks/flying-photo-booth/blob/master/flying-photo-booth/res/values/strings.xml
• https://github.com/groundupworks/flying-photo-booth/blob/master/party-photo-booth/res/values/strings.xml
• https://github.com/groundupworks/wings/blob/master/wings-dropbox/src/main/res/values/strings.xml
• https://github.com/groundupworks/wings/blob/master/wings-facebook/src/main/res/values/strings.xml
• https://github.com/groundupworks/wings/blob/master/wings-gcp/src/main/res/values/strings.xml

[benhylau]

French translation by Pascal, to be ported into XML: https://docs.google.com/spreadsheets/d/1oU9za0cehRsNLGvjjI1rdaAOHzx259leGO6aF0fknPI/edit?usp=sharing