Add "about" information to the viewer,
including an attribution line in the title bar
and plugin information in an about dialog.
Let viewer be loaded without a plugin as well.
Merge pull request #233 from vandenoever/typechecking

Add more type information.
Merge pull request #214 from adityab/about-dialog

Add a simple 'about' dialog to viewer.
Add OperationRouter.getHasLocalUnsyncedOpsAndUpdates/OperationRouter.unsubscribeHasLocalUnsyncedOpsUpdates
Fix condition when to log on replies to Pullbox servers
Fix collabeditor.js to use the right memberid and sessionid on server.leaveSession(...) call
check if localSelectionView exists in gui.SessionView.onCursorMoved, as done for localCaret
make failCb a needed argument to Server.joinSession and Server.leaveSession
Catch failing playback of operations or unknown ops coming from server
Add OperationRouter.getHasSessionHostConnectionAndUpdates/OperationRouter.unsubscribeHasSessionHostConnectionUpdates
Catch any errors in the OperationRouter & calling the server and report in separate callback
Export errors and other oprouter states in the Editor API, experimental use in collabeditor.js
For OperationRouter turn explicit subscription methods into generic ones + explicit state getters
Add API dox for Editor.addEventListener, with possible event ids and error codes
Merge pull request #239 from kossebau/escalateErrors

Escalate errors and state change events into the Editor API
First version of prototype XML editor.
style improvements
many fixes and added XmlCaret class
Add previews of the transformed xml.