Return consistent version of a US Street Address using stringr::str_*()
functions. Letters are capitalized, punctuation is removed or replaced, and
excess whitespace is trimmed and squished. Optionally, street suffix
abbreviations ("AVE") can be replaced with their long form ("AVENUE").
Invalid addresses from a vector can be removed (possibly using
invalid_city) as well as single (repeating) character strings ("XXXXXX").