[2.3.x] + (additional commit for) implement improvement #1662
https://java.net/jira/browse/GRIZZLY-1662
"Check that kernel ThreadPoolConfig size is big enough to run configured number of SelectorRunners"
[2.3.x] + fix issue #1663
https://java.net/jira/browse/GRIZZLY-1663
"NPE when registering a servlet in grizzly-httpservice"