Adds new Elsevier dependent styles.

As a result of this:
a) Deletes some independent styles (now they have been consolidated as
   dependents)
b) Deletes some dependent styles: they use a bit different name
c) Updates some other styles: they had a template a non-existing style
   (usually cell, not just a dependent style)
d) promotes dependent/therapeutic-advances-in-neurological-disorders.csl
   to a real style using the previous referenced style