if cookies are rejected, try passing sessionId in url (as expected by java servlets)

NB: also configuring CAS to not redirectAfterValidation since:
- it needs cookies
- it is useless for /rest/login which is a web service
js: specific error message in case of WS error 503
for server side templates, use {{serverSide.xxx}} instead of simply {{xxx}}

this will allow more powerful things and is clearer regarding angularjs
implement service-side-xxx directives to handle wsgroupsURL css/js + cache busting (aka fingerprinting)

NB: the cacheBuster adds ?v=<timestamp> to urls, which is not best according to https://developers.google.com/speed/docs/best-practices/caching
    but it should be quite good for our needs (and better than nothing!!)
implement service-side-concat & service-side-angular-templates directives

it allows concat of js files + angularjs templates