Minify demo: use Eclipse Orion editor.

https://code.google.com/p/esprima/issues/detail?id=337
Import Esmangle version 0.0.10-dev.

https://code.google.com/p/esprima/issues/detail?id=337
Minify demo: use Esmangle to compress further.

https://code.google.com/p/esprima/issues/detail?id=337
Minify demo: make variable shortening (mangling) optional.

https://code.google.com/p/esprima/issues/detail?id=337
Minify demo: customize mangling pipelines.

Not every pipeline is customizeable at the moment, we pick some simple
optimizers first. By default, all possible Esmangle pipeline will be
used, some of them will be excluded depending on the checkboxes.

https://code.google.com/p/esprima/issues/detail?id=337