Mon 30 June 2014 21.10 BST
1. Tiny changes (including a bug fix in the Model Properties dialogue)

Mon 30 June 2014 19.20 BST
1. The Model properties button in the Toolbar now enables the user to edit the model name, title, description and author.

Mon 30 June 2014 14.40 BST
1. Major overhaul of saving to/loading from file
2. Now use model label (actually model.meta.name) for display purposes, but ID also usually visible (e.g. in model menu; Run Control header)
3. All New models are labelled 'noname' -not trying anything clever with giving each one a number.  But ID can be used to discriminate (in the unlikely event that user makes several new models and does not re-label them when saving).
4. Added a 'Clear Local Storage' button in footer - for emergency use.
5. Add last-update date/time to footer (has to be edited manually), plus link to this change log.
6. Loading an incomplete/incorrect model (from file or Local Storage) should now be more robust - simulate() has a try-catch on it to pick up any failure when executing generated code.
7. Only file tabe in open/save dialogues work: user gets a message thatthe others are not yet operational.
8. Label-edit div is now closwed by clicking on a toolbar snode or arc button.

TODO:
1. Still some minor funnies when doing New after loading and running a amodel (e.g. graph and sliders still)
2. End-time issue still needs sorting.