create a SiteFeaturizer class that describes single site w. LOBSTER output

• LOBSTER charges
• sitewise BWDF
• coordination environment info obtained from LobsterEnv as ce, csm
• statistical ICOHP features of its bonds (min, max, mean, std..)
• make optional to also featurize COHPCAR (b/ab percentages, ..)

create a PairFeaturizer class that describes single interaction w. LOBSTER output

• compute stats from the two SiteFeaturizer outputs, e.g. LOBSTER charge differences
• also include outputs fr. SiteFeaturizers directly -> need to think about site ordering!
• ICOHP of bond
• make optional to also featurize COHP of bond