Translations:New Template System in LS3.x/105/en

Few remarks:
 * name: will be used as a key in the db. So it must be unique, and it should not have any special chars (no spaces). Note that cases will not be taken in account
 * Title: will be used to display your theme name in the different lists. It can have special chars
 * description: will be used in the main list of survey theme. It can contains special chars, and even HTML code by using
 * extends: optional, it defines the parent themes. So if any file is not present in this theme (twig/js/css/jpg, etc) it will look for it in the parent theme