Prepare for adding dutch language

.tx/config

app/src/main/res/values-nl/strings.xml

app/src/main/res/values-nl/strings_certificates.xml

app/src/main/res/values-nl/strings_contributors.xml

app/src/main/res/values-nl/strings_defaults.xml

app/src/main/res/values-nl/strings_error.xml

app/src/main/res/values-nl/strings_format.xml

app/src/main/res/values-nl/strings_info.xml

app/src/main/res/values-nl/strings_messages.xml

app/src/main/res/values-nl/strings_preferences.xml

app/src/main/res/values-nl/strings_settings.xml

app/src/main/res/values-nl/strings_setup.xml

app/src/main/res/values-nl/strings_status.xml