BAZYNGO-1801: suppressed some warnings
BAZYNGO-1801: factored the (informative) target URL generation, used by
RewriteRegistry REST endpoint into RewriteTarget class.
BAZYNGO-1801: moved actual rewriting action into RewriteTarget class.
This helps to contain the knowledge about hardcoded "/ledge" servlet
path into single place.
BAZYNGO-1801: refactoring: preparing for rewrites targetting a view
instead of of NavigationNode
BAZYNGO-1801: An extension for LedgeRewriteFilter mechanism allowing
redirecting to arbitrary ledge-web views.