Moved methods of ITabbedDisplayMgr into IDetailPaneDisplayMgr and deleted ITabbedDisplayMgr.
Removed TDetailFrame to remove reference to ITabbedDisplayMgr and updated method comments.
Modified TMainDisplayMgr, replacing details pane manager cast to ITabbedDisplayMgr with casts to IDetailPaneDisplayMgr.
Also changed TMainDisplayMgr so that Ctrl+Tab and Shift+Ctrl+Tab key-presses always result in change of detail pane tab, regardless of whether overview frame has keyboard focus.
