Destructuring (Harmony) / rewrite run-tests

This changes bring a destructuring variables support.

I added a local version of esprima harmony branch. It maybe not a good idea, so I add a --es6 flag to require a local esprima and to run es6 tests.

```
node --harmony defs-wrapper --es6 tests/es6-destructuring.js
node run-tests --es6
```

+.gitignore

Also I rewrite run-tests:
1. To run tests in queue (in Windows node.js has is a strange behavior with stderr when it run few subprocess). 
2. Rewrote the string compare to reduce OS stdout/IDE settings impact.