0.4.4 README.md revised.
0.4.3 README.md revised.
0.4.2 A line is added to README.md.
0.4.1 README.md is slightly changed.
0.4.0 A function data() is introduced.
0.3.0 A function listWoo() is replaced with dataWoo().
0.2.0 A function <dataset>.load() is replaced with dataWoo('<dataset>').
A function help(<dataset>.load) is replaced with dataWoo('<dataset>', description=True).
A function <dataset>.wooldridge() is replaced with listWoo().
README.md changed accordingly.