Added a flexy install command

Here's some examples:

Database validation

![screen shot 2013-10-10 at 10 01 35 am](https://f.cloud.github.com/assets/874403/1306809/a176491e-31b5-11e3-9e4e-24cb861abfdb.png)

Administration setup. Used to create the default backend administrator.

![screen shot 2013-10-10 at 10 00 31 am](https://f.cloud.github.com/assets/874403/1306810/a17a93ac-31b5-11e3-94f5-4a76f756d96e.png)

Exceptions handling

![screen shot 2013-10-10 at 9 59 50 am](https://f.cloud.github.com/assets/874403/1306811/a17a73ea-31b5-11e3-918e-796b853dd70f.png)
![screen shot 2013-10-10 at 9 58 31 am](https://f.cloud.github.com/assets/874403/1306812/a1802920-31b5-11e3-8b8f-392d6dcc1dfe.png)