Fixed sorting versions #60.

Fixed sorting versions #60.
Refactor Bowerphp::getPackageInfo.

`./bowerphp info jquery`

```
Available versions:
- 2.1.1
- 2.1.1-rc2
- 2.1.1-rc1
- 2.1.1-beta1
- 2.1.0
- 2.1.0-rc1
- 2.1.0-beta3
- 2.1.0-beta2
- 2.1.0-beta1
- 2.0.3
- 2.0.2
- 2.0.1
- 2.0.0
- 2.0.0-beta3
- 2.0.0b2
- 2.0.0b1
- 1.11.1
- 1.11.1-rc2
....
```