Correctly show side colors when {row,col}_cluster=False

Addresses https://github.com/mwaskom/seaborn/issues/366#issuecomment-64209205

```
import seaborn as sns
import numpy as np

data = np.random.randn(20).reshape(4,5)

row_colors = sns.color_palette(n_colors=data.shape[0])
col_colors = sns.color_palette(n_colors=data.shape[1])

sns.clustermap(data, row_colors=row_colors, col_colors=col_colors, col_cluster=False, row_cluster=False)
```

![image](https://cloud.githubusercontent.com/assets/806256/5167623/80c64eee-73c7-11e4-84cf-327e24739e5c.png)