Extend new categorical ordering rules to FacetGrid

[mwaskom]

FacetGrid now uses utils.categorical_order to determine default order for the row, color, and hue variables. This means that all categorical ordering in seaborn should follow the same rules. Please open an issue if you run into something that doesn't.

Closes #361

[Bharat05]

I was expecting seaborn to sort the categorical variable on x-axis. Please help.

titanic_df = pd.read_csv('train.csv') #from Kaggle Titanic Dataset
deck = titanic_df['Cabin'].dropna()
levels = []
for level in deck:
    levels.append(level[0])
cabin_df = DataFrame(levels)
cabin_df.columns = ['Cabin']
sns.factorplot('Cabin', data = cabin_df, palette = 'summer', kind = 'count')