- Add rational on client export
- Add external url model
- Update language model
-Update template file

-fix bug of limiting file size for sending pic
- new language templates
-new schemas for objectives and alternatives
- controler for alternatives on client


Todo 
- controler for objective on client

- Correct model bug for empty id in Survey
- Add possibility to drop survey database
- Get token related to one survey_id
- Get test token of survey_id

- Add template files func : template variable and translation can be saved in public/template
- Templates files are automatically loaded if database is empty
- Possibility to upload and download templates

- Add possiblity to check if an user exist and create one if not the case
- Correct enable/disable survey
- correct startup.sh

This version autorise the storage and modification of surveys
Client functionalities for reading and sending data or results