Add Bioguide resolution using legislators YAML

If the Bioguide ID isn't found in the member page, resolve it from the values in the YAML file.
Resolves in this sort of order:
last, first
last, first middle
official name
last, nickname
last, first middle-initial.
last followed by , first
ballotopedia name
wikipedia name
last, firstname
last, firstnam
last, firstn
...
last, fi
last, f

Didn't resolve Bioguide IDs for four people.

Bradley, Byrne 113/RP/Bradley -> because GPO has bad data. He's really "Byrne, Bradley".

GPO data should be fixed (how to report?), but should we add a final resolution case for switched names?

These three aren't in the YAML:
Chiesa, Jeff 113/SR/Chiesa
Radel, Trey 113/RP/Radel
Young, C. W. Bill 113/RP/Young

Chiesa left in 2013, Radel left in 2014, Young died in 2013.

TODO: Add caching of downloaded pages, rate limiting.
See https://github.com/unitedstates/congress-legislators/issues/160#issuecomment-34833782