Facelift for Rule and Style UIs.

A redo of the Rule and Style UIs.

* Redo proportions
* Set the Description text box to wrap words (and not just characters).
* **Important**: Avoid creating the rule panel twice (getComponent() was called in the initialize method -- [see the code](https://github.com/irstv/orbisgis/pull/481/files#L0L200)).

See #480.

#### Before
![old_rule](https://f.cloud.github.com/assets/2470768/811153/8d7fa0e0-eecb-11e2-976a-cb75c912444b.png)
![old_style](https://f.cloud.github.com/assets/2470768/811154/8fa2aa0c-eecb-11e2-9c7a-558723683f23.png)

#### After
![new_rule](https://f.cloud.github.com/assets/2470768/811156/951eceac-eecb-11e2-9891-57cc94fe00db.png)
![new_style](https://f.cloud.github.com/assets/2470768/811158/96c4e4f8-eecb-11e2-999c-3a80cc83d657.png)