Feature: We want a Adorsys Theme V1 with more Layout & Structure

Working on
- #86

we discovered that the base layer proposed by the adorsys theme v1 is not rich enough to create a structure. We need to enhance the base adorsys theme with more layout & data:
- more pages / templates
- => define which pages we need to have something working fine & being helpful too.
- => reminder: not all templates will be displayed, so we might still have them, even though we won't need them
- extended classes (from the core moodle)
- base styling & css structure
- => we'll need some css classes, even if they're not used. Child themes might make use of it.

To ease development's lifecycle, we'll make the base theme (v1) extends boost.