PropertyResolver causes memory leaks with proxies

When using proxies for properties, a memory leak occurs.
The ConcurrentHashMap classesToGetAndSetters doesn't have an eviction policy and fills up with proxies who do not get
garbage collected.

Build a page which uses proxies as properties, every time a new session is initiated, a new proxy (a new proxy is a new class) of the same property is created and added to the map.
if the proxy is create by a remote jvm you also get a classloader leak.