Output of external tools appears in "General Messages" pane

Applies to both "External Tools" menu and "Execute custom commands" locator filter.

• This pane should display "general messages", like its name suggests. App output is unexpected there.
• stdout and stderr all appear in the same color (unlike the Application or Build panes)
• There is no way to stop the executed tool (that's the most annoying issue).

I suggest using the Application Output for this.

The problem is that this pane is in the ProjectExplorer plugin, and external tools are in Core and Locator, which cannot depend on PE. Moreover, AppOutput has some substantial dependencies on PE (RunControl, which itself uses RunConfiguration etc...)

Ideas?