Replace all stream-based IO with non-blocking NIO-based implementation.  Still a fair amount of cleanup to do, particularly in the SSL handler, which is not very robust, and exception handling in general.  All core functionality appears to be working fine though.

git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4842 3789f03b-4d11-0410-bbf8-ca57d06f2519
22 files changed