remove useless imports
Deprecated setting of values on annotations. Annotations should be read only. This feature will be removed with 5.0.0.
refactor annotations parsing:
 * the parser should return a map of annotations, not some internal structure where it collects information while parsing
 * simplify annotation factory, must not cache parser results but can now put the final annotations directly into the cache
don't store argument name separately, not required any more
get rid of annotation targets, had no external meaning anyway
optimize
decide to remove value setting entirely and move up to 5.0.0
introduce method to return a list of all annotations on an element
add note about new feature