layout.html ignores ALA head.html

[vjrj]

Although ALA head.html is empty other LA portals (like Portugal or Spanish portals) or ala-install demo role use it to add custom code. The ala-bootstrap3 HeaderFooterTagLib loads it.

In CAS, head.html is not included in its layout as this repository uses a different code to generate the layout.

As a workaround we add script and link code in the banner and/or footer.

Would be nice if:

<ala:head></ala:head>

is also included in ala-cas-5 layout.html to have the same behavior like the rest of the ALA modules (included apikey and userdetails).

cc @rpfigueira