ve.ce.ProtectedNode

Objective:

Generalize the shield and phantom magic, so we can use it for pretty much
any node we like. Usually this will be used with generated content nodes,
but also with aliens (of course) and possible other stuff in the future.

Bonus:

Also fixes a bug in DM that would crash VE when you selected to the end
and hit backspace.

Changes:

*.php
* Added links to files

aliens.html
* Added attributes to aliens to make them aliens again

ve.ce.AlienNode.js
* Moved shield and phantom functionality to ve.ce.ProtectedNode

ve.ce.AlienNode.js, ve.ce.MWReferenceListNode.js,
ve.ce.MWReferenceNode.js, ve.ce.MWTemplateNode.js
* Mixed in ve.ce.ProtectedNode

ve.ce.Node.css
* Reorganized styles and updated class names
* Added simple light blue hover with outline (using inset box shadow) for
  protected nodes, same style as before for aliens

ve.ce.Surface.css
* Moved phantom styles to ve.ce.Node.css

ve.ce.BranchNode.js
* Moved call to setLive(false) to happen before detach() so that the
  surface object is still available and events can be disconnected

ve.ce.BranchNode.js, ve.ce.Document.js, ve.ce.js, ve.ce.Surface.js, ve.ce.SurfaceObserver.js
* Adjusted CSS class names

ve.ce.Node.js
* Moved shield template to ve.ce.ProtectedNode

ve.ce.ProtectedNode.js
* New class, mix into another class to protect it from editing

ve.ce.RelocatableNode.js
* Renamed temporary surface property to relocatingSurface to avoid
  confusion when debugging

ve.ce.Surface.js
* Moved phantom template to ve.ce.ProtectedNode

ve.dm.Transaction.js
* Fixed bug where most of the internal list was being deleted when the
  end of the document was selected and the user pressed backspace

Change-Id: I2468b16e1ba6785ad298e38190e33493135719c3
Merge "ve.ce.ProtectedNode"