PrivilegedAction can executed with generics

I did some test with an app that uses commons logging and log4j. I removed log4j and commons-logging jar and put slf4j-api + jcl-over-slf4j and log4j-over-slf4j. All works fine.

Can you suggest another test to see if is really compatible with jcl and log4j? Generics are compiled as <Object> but is better if we make some tests.

If you appreciate this pull request I think that I can convert all other collections to use generics, if you want. Do you think that we don't have any problems to migrate projects like log4j-over-slf4j to use generics?

Best regards and thank you