[Ide] Moved dock notebook to own namespace.
[Ide] Implemented container docking.
[TabStrip] Fixed tab strip drawing.
[Docking] Fixed active document system.
[Docking] Reworked document docking gui model a bit & reimplemented
docked tab closing.
[Docking] Prevent main notebook from destruction.
[Ide] Fixed file tab close commands.
[Docking] Added missing file.
[Docking] Fixed placeholder window.
[Docking] Floating windows are now listening to key events.
[Docking] Fixed active control command target handling.
[Docking] Set tab title when moving documents.
[Docking] Completion window is now transient for the editor toplevel
window.
[Docking] Fixed some minor issues.
[Docking] Fixed active document focusing on os x.
[Ide] Fixed active tab control & ensured that's defaulted to the main
tab control.
[Docking] Workbench title now shows the active file in the workbench
tab control instead of the global active file.
[Docking] Placeholder window is now always on top.
[Docking] Floating windows are now presented to the user if a child
document gets focus.
[Docking] Closing windows now closes all inside documents.