Typo in the docs [quick fix 😄]

[rakreek]

In pylift/docs/eda.rst there is a typo in the LaTeX. It should swap \elem for \in to get the symbol ∈ in the following line:

\text{WOE}_{ij} = \log \frac{P(X_j \elem B_i | Y = 1)}{P(X_j \elem B_i | Y = 0)}