A pretty-printer for Clojure data structures.

Based on the algorithm described in "Pretty-Printing, Converting List
to Linear Structure" by Ira Goldstein (Artificial Intelligence, Memo
No. 279 in Massachusetts Institute of Technology A.I. Laboratory,
February 1973).

Here's how the algorithm (as implemented in this namespace) works:
given a form, if there is enough space remaining on the current line
to print the entire form without any line breaks, do so. We call this
style of printing the "linear" style. The printing functions (prn et
al.) in clojure.core always print in the linear style.

If there is not enough room to print in the linear style, print the
form in "miser" style instead. In the miser style, we insert a line
break after each form (except map keys, if there is enough room to fit
the entire value on the same line), and indent each form according to
the current nesting level.