[Debug] Added code context when an arror occurs

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | I guess
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

![debugger](https://f.cloud.github.com/assets/408368/2230921/90e95ee8-9b09-11e3-8af1-aa6d5d536b45.png)