IMP: tabulate viz additions

[lizgehret]

A few nice-to-haves in composition's tabulate visualization:

1. Description on log-fold change positive vs. negative meaning (enriched vs. depleted relative to the chosen intercept i.e. reference level(s))

• ln(A/B) = ln(B) - ln(A)

• A > B -> + (enriched)

• A < B -> - (depleted)

2. Description with: what W score is (lfc/se), what the chosen reference level is (i.e. intercept)

[lizgehret]

Targeted for Feb release