[Feature Request] Configurable console activation

[wti]

Currently the ANTLR console always activates and steals focus when anything is written to it, which alters the user's UI (when mostly the messages are: all good!).

This should be disabled, configurable (via preferences), or settable in the console UI (see e.g., the java console with buttons for activation on stdout or stderr).

The operative line is DefaultConsole:44