Some UI consistency work
* Add main Toolbar

Some coding convention work
* Add 'Navigation' menu für keyboard navigation actions. Mainly usefull to look up shortcuts... And it saves a call to 'addAction(action)' for those actions, as their shortcut aren't registered otherwise.
* Add 'Navigation' toolbar for keyboard navigation actions.
* Add tooltips to keyboard navigation actions.
* Rename initKAction() method to setupActions(); towards best practice for all of KDE Games...
* use 'actionCollection()->add<QAction>(name, this, SLOT(slotName()))' style action creation. This seems to be the preferred way now.
* Added some comments

Some 'use available technologies' work
* Use XMLGui Action states for enabling/disabling 'undo'
* Move icon, shortcut, whatsThis and text declarations for actions into <ActionProperties> in the xxxui.rc file. Seperates Usablility and UI consistency concerns from coding. Not sure if the i18n work nice, though.

Please report if I've broken something;-)