Bind `fill-paragraph-function' to `lisp-fill-paragraph'

* clojure-mode.el (clojure-mode): Bind `fill-paragraph-function'
to `lisp-fill-paragraph' instead of `clojure-fill-paragraph'.
(clojure-fill-paragraph, clojure-docstring-indent-level)
(clojure-fill-docstring): Delete.
Merge pull request #225 from bzg/master

Bind `fill-paragraph-function' to `lisp-fill-paragraph'