CocoMUD client

Fix #147: adding new characters doesn't automatically check the default character checkbox

Bring #157: add the anti-idle feature

Implement #158: the notepad dialog doesn't hide the client window anymore

Fix #152: importing a world from a file fails

Update the project license information

Fix #127: the notification counter remains down for empty messages

Various esthetical fixes

Fix #136: remove the dependency of the sharp engine on world, add it to sessions

Automatically alter the TTS in the SharpScript console

Add the SharpScript console