Fix some web socket JSR compliance issues
[UNDERTOW-310] Only prompt for SPNEGO authentication if the server has an identity for the host in the request.
[UNDERTOW-317] Where a redirect port is unavailable log an error and use status code 500.
Merge pull request #257 from darranl/UNDERTOW-317/master

[UNDERTOW-317] Where a redirect port is unavailable log an error and use status code 500.
Merge pull request #255 from darranl/UNDERTOW-310/master

[UNDERTOW-310] Only prompt for SPNEGO if server configured for host in request.
Fix bug in idle timeout conduit
Send correct message type
Get buffer size from pool
Fix framed channel flush implementation
Support running in JVM bootstrap class loader
Make session listener work correctly under security manager
Merge pull request #259 from trask/bootstrap-class-loader

Support running in JVM bootstrap class loader