json : use double quotes instead of single quotes

[Marc-pi]

we're encountering frequent issues with json and gettext values : in case of latin language, there is a frequent usage of apostrophe ', that breaks code

example
module/user/template/front/account-index.phtml

if (result.email_error === 0) { this.emailInitVal = result.email_value; this.$email.after('<span class="help-block">' + result.email_message + '</span>'); }

need to be replaced to

if (result.email_error === 0) { this.emailInitVal = result.email_value; this.$email.after("<span class='help-block'>" + result.email_message + "</span>"); }

=> so there are a lot of area in Pi code where we have to make this change
=> and we must take the abbit to use double quote like this in your json outputs