weights misbehave with time restrictions

[rfl-urbaniak]

          Really great functionality already, some remaining design stuff to figure out, but already quite powerful!

I'm happy for this to be merged, though there are some things to be fixed -- please make issues for things that will be fixed in future PRs.

In addition to what's in my and Andy's comments:

• In similarity_demo.ipynb (see codeblock below), the FipsQuery option outcome_comparison_period doesn't work right. Setting it to (2003, 2010) yields weights between 2001 and 2008. Setting it (2010, 2023) yields weights bt 2001 and 2011. (2003, 2019) -> (2001, 2017).

f  = FipsQuery(42001, "gdp", lag = 0, top =5, time_decay = 1.06, 
               outcome_comparison_period=(2003, 2010), outcome_percentile_range= (40,100))
f.find_euclidean_kins()
display(f.plot_weights()) 

• Also debug the FipsQuery option outcome_comparison_period for the case of multiple feature groups. This behaves badly (different times for the different variables, neither what is specified):

f  = FipsQuery(1007, outcome_var = "gdp",
               feature_groups_with_weights= {"gdp": 1, "population":1}, #with one feature group only
               # weights 1-4 won't make a difference
               lag = 0, top =5, time_decay = 1.5, outcome_comparison_period=(2003, 2010))

Originally posted by @emackev in #36 (review)