Remove DataBinder from GraphQlArgumentBinder

DataBinder is not a great fit to bind GraphQL arguments which
are essentially a (structured) map of maps and collections, rather
than a (flat) map of property values with JavaBean paths.

We already navigate recursively the GraphQL arguments map, which
corresponds to the target Object structure, creating values, so all
we have to do is check for matching bean properties at each level
and set them.

See gh-516

Author: rstoyanchev