Added a message log dialog which supports page up/down, home/end, up/down and...

Added a message log dialog which supports page up/down, home/end, up/down and mouse wheel. Activate it by clicking on the log or pressing ctrl+m


git-svn-id: http://svn.net-core.org/repos/t-engine4@3374 51575b47-30f0-44d4-a5cc-537603b46e54