Erster Versuch. Klappt noch nicht so richitig.

Muss ich mir tehoretisch mal genauer anschwaiuen. Womoeglich matcher-Functions
fuer alle zu checkenden Entitaeten: ( string -> bool )
GENERIC find_elements_by - function, which eats a macther-func and generates a matcher.
second example for generated find_elements_by - stuff
Now the lookup-functions are created generically.
using generic lookup-functions reduced parers.ml by 196 lines ( from 946 to 750 lines).
Merge branch 'refactor_find-elements'

Creating the lookup-functions generically now;
could reduce parsers.ml from 946 to 750 lines this way,
which means 196 lines less code :-)