Updated Debug class

Colorized debug output like var_dump output. See screenshots.

**Sandart `var_dump` output:**
![var_dump](https://f.cloud.github.com/assets/1256298/1506849/4296dc1c-4950-11e3-9d3d-f5b488b26695.png)


**New `Debug::vars` output:**
![debug_vars](https://f.cloud.github.com/assets/1256298/1506853/5437e376-4950-11e3-962f-5c822df84ffa.png)