/**
* Tracking management:
*
* without header:
* https://dns.xx/trk/pathtofile?alias=anonymous&uuid=1b506f71-1bff-416c-9057-cb8b86296f60&src=btnregister&version=1&lg=fr
*
* with header
* https://dns.xx/trk/pathtofile?src=btnregister&version=1
*
* where pathtofile is a ressource accessible from https://dns.xx/pathtofile
*
* We get :
* alias: if athenticated from header else anonymous
* uuid: a uuid v4 générate the first time a web page is open on a browser
* src: source action that trig this get
* version: can be an int, date or any version of the src
* tm: optionnal is a timestamp of action when it is not immediate (offline app)
*
* html usage to track a loading page or email when a picture is load
* using apxwebapp in /src/ we got:
*
*
* using html + apx.js (or at least with header {xalias,xuuid,xlang})
*
*
*
* in js action:
* or
*
*
* will hit an eventlistener
* axios.get("https://dns.xx/trk/cdn/empty.json?alias=anonymous&uuid=1b506f71-1bff-416c-9057-cb8b86296f60&src=btnregister&version=1");
*
*
* or if no js available (example:email or pdf document)
* *
*
*
* if you use apx.js :
* in html add in
*
* using html + apx.js (or at least with header {xalias,xuuid,xlang})
* 
*
*
*
* if you use apx.js :
* in html add in