Add locale/translations for survey plugins

[becky-gilbert]

Summary

The video consent plugin supports translations via a locale parameter that grabs translations from the appropriate yaml file and inserts translated text into the plugin's handlebars template. We have translations for the hard-coded text in the survey plugins: ConsentSurveyPlugin and ExitSurveyPlugin. Now we need to update those plugins so that they accept a locale parameter and grab the text from the yaml files. This may need to be set up in a different way (vs the video-consent/config plugins) because the hard-coded survey text is inserted via JSON that is passed to the SurveyJS package, rather than through a handlebars template.

To do:

• Add locale parameters to ConsentSurveyPlugin and ExitSurveyPlugin Exit Survey i18n #97 SurveyJS locale #98
• Set up the plugin to retrieve text from the appropriate translation file, rather than hard-coding it into the survey JSON. Exit Survey i18n #97 SurveyJS locale #98