Initial commit to support world-clouds visualization

[selimelawwa]

closes #12
Basic implementation for word-clouds visualization
Add wordcloud to list of in "requirements.txt" file

[jbesomi]

Thank you Selim!

It may be opportune to have as input a pd.Series rather than a pd.Dataframe.

Also, for joining the text we may want to use:

>>> import pandas as pd
>>> s = pd.Series(["a", "b", "c"])
>>> s.str.cat(sep=' ')
'a b c'

Can you also add some unittest? You can look at the official world_cloud tests.

[selimelawwa]

I have changed the function have as input a pd.Series @jbesomi .

Regarding unit tests. I have checked official world_cloud tests. However current implementation of the word cloud method would not allow for implementing similar tests. Maybe we can have an underlining method _get_world_cloud which gets the WordCloud object which we can then test for words ..etc?

Do we only need to test the words in the generated word cloud? What else would you want to test?

[jbesomi]

Thank you. Closing for now.