Recognize directive prolog 'use strict' for strict mode.

Patch by Yusuke Suzuki <utatane.tea@gmail.com>.

http://code.google.com/p/esprima/issues/detail?id=161
Generate code from expression node in the syntax tree.

Patch by Yusuke Suzuki <utatane.tea@gmail.com>.

http://code.google.com/p/esprima/issues/detail?id=155
Direct object initialization.

This optimizes property access. As discussed in
http://code.google.com/p/esprima/issues/detail?id=78
Optionally preserve raw literals.

This adds a 'raw' property to all Syntax.Literal nodes. We ignore this property
for the SpiderMonkey compatibility tests, as the Mozilla parser API does not
return raw literals.

- Moved all Syntax.Literal creation to separate function.
- Added a 'raw' option.
- Added checkbox for 'raw' option in parser demo.
- Updated test code to run with enabled 'raw' option.

Issue: http://code.google.com/p/esprima/issues/detail?id=78
Add location info to catch clause in a try statement.

http://code.google.com/p/esprima/issues/detail?id=6
Add location info to variable declarator node.

http://code.google.com/p/esprima/issues/detail?id=6
Add location info to the switch case node.

http://code.google.com/p/esprima/issues/detail?id=6
Add location info to new expression node.

http://code.google.com/p/esprima/issues/detail?id=6
Add location info to function expression.

http://code.google.com/p/esprima/issues/detail?id=6
Add location info to variable declaration node.

http://code.google.com/p/esprima/issues/detail?id=6
Add location info to object property.

http://code.google.com/p/esprima/issues/detail?id=6
Update copyright info.
Add location info to object property key.

http://code.google.com/p/esprima/issues/detail?id=6
Mention Mozilla Reflect compatibility.
Strict mode: some delete operations must trigger a syntax error.

Patch by Yusuke Suzuki <utatane.tea@gmail.com>.

http://code.google.com/p/esprima/issues/detail?id=165
Simplify the process to construct the raw literal.

No need to store the raw value in the token, we can always extract it
from the source since the token always has the range info.

http://code.google.com/p/esprima/issues/detail?id=78
Strict mode: duplicated property should trigger a syntax error.

Patch by Yusuke Suzuki <utatane.tea@gmail.com>.

http://code.google.com/p/esprima/issues/detail?id=166
Prioritize different syntax nodes in primary expression.

Check for the most common cases first (identifier, string, number)
before handling everything else.

On the benchmarks suite, Firefox 10 show 18% speed improvement.

http://code.google.com/p/esprima/issues/detail?id=171
Generate code from statement nodes.

Patch by Yusuke Suzuki <utatane.tea@gmail.com>.

http://code.google.com/p/esprima/issues/detail?id=168
Fix regression in IE <= 7.

Patch by Yusuke Suzuki <utatane.tea@gmail.com>.

http://code.google.com/p/esprima/issues/detail?id=78