[2.3.x] + fix copyright headers
[2.3.x] Backport changes for https://java.net/jira/browse/GRIZZLY-1649 (Provide a mechanism to specify a factory class for the default memory manager).

(cherry picked from commit 501e339ce3c3196ef1532fec8288616b793ed476)
[2.3.x] + fix issues found when setting PooledMemoryManager as default mm