Issue #750

This is just an IntelliJ refactor, using EventBus in place of
DMDircMBassador whenever possible.

Stop swimming against the tide and accept what most of the rest of
the world does.

While it adds an annoying depth to the actual source code, it makes
the root directory nicer (no more 'test-res' dirs), means we don't
have to override the gradle config, and makes it nicer to work in
IDEA 2016.1.

Events aren't unread and shouldn't affect the display colour of
a window if they're hidden.

Instead of wrapping the source event and modifying it, they are
now proper events that are displayed themselves (and the original
message is suppressed).

This allows highlights to be formatted differently.

Issue #669

Add defaults for the old colours instead of horrible lime green.

Should probably improve this to only raise an event when the
values change, but will do for now.

Needs to allow configuring of the colours, and provide events
for notifying the UI.