Modernize 2013

The contents of the modernize-2013 branch try to bring the tiddlywebwiki code up to date with modern TiddlyWeb convention in both coding style and data handling. There are a small number of major changes (listed below) and various small tidies scattered throughout the code. The major changes include:

* Update README, add COPYRIGHT and other general doc and text information updates
* Use the Tiddlers collection concept in the serialization
* Update to get the `update` twanager command from `twp.instancer`
* Use a locally kept `empty.html` and **pin its version to 2.6.6** since [2.7.0 does not work](https://github.com/TiddlyWiki/tiddlywiki/issues/115)
* Move the required TiddlyWiki plugins (`TiddlyWebAdaptor` etc) into the repo instead of hosting them in a different repo. Though they _can_ be used in other contexts this is the only one in which they actually **are** used so may as well keep things clear.

All of these changes (above) result in no actual functional changes in the system: things continue to work the same. The only functional change is that the "browse" link that shows up in the no javascript section is now calculated form the tiddlers collection and is not a fully qualified URI, it is relative to the current host.

This branch intentionally makes no major changes so as to lay in a solid foundation for doing various cleanups later. Those cleanups include possibilities such as:

* doing the [friendlywiki thing](http://groups.google.com/group/tiddlyweb/t/7aec575989d0359b)
* linting the tiddlywiki plugins and bringing them up to modern standards
* fixing some of the bugs in binary handling

If anyone reviewing this has comments on that sort of stuff please take it to the groups or   issues.

I'd appreciate some input from @FND, @pmario, @Jermolene, @ericshulman to make sure I've not missed anything obvious in these changes. The tests have high coverage and a test instance is working just fine, but always nice to have some additional eyes. Thanks.