Fix \v being treated as v in IE < 9

IE < 9 treats '\v' as 'v' instead of a vertical tab ('\x0B').
Read more: http://mathiasbynens.be/notes/javascript-escapes

https://code.google.com/p/esprima/issues/detail?id=405
Fix variance unit conversion.

If all values are scaled by a constant, the variance is scaled by the
square of that constant.

https://code.google.com/p/esprima/issues/detail?id=397
Parser demo: trigger the parsing when using the specialized URL.

Also, ensure that the tree is updated after that widget is available.

https://code.google.com/p/esprima/issues/detail?id=404
Merge branch 'master' into gh-pages