seq is redundant here

since all usages of alphabet will work the same way on
the string as well (i.e., seq gets called implicitely).
whitespace
Reformat parens & such

Mostly

- removed spaces where not typcial
- no closing brackets on their own line
- consistent indentation (via emacs clojure-mode auto indent)
kebab-case

This is definitely idiomatic, and I personally think it's prettier.  I
think it's only avoided in other languages because the lexer can't
handle it.
s/.length/count/