assorted updates to POTUS

moved the array outside of the handler
moved the wikipedia links to `https://`
urlencoded the link hrefs
added the trigger "president of the us"

reformatting for clarity. tests updated to match changes.
Merge remote-tracking branch 'remotes/origin/pr/206'

Updating to optimizations.
Added support for natural language queries from 1-20.
Added 3 new tests to test file.