eval-expression-print-level|length are not respected

[jdtsmith]

Eros captures the return value of the prin1 call made by elisp--eval-last-sexp-print-value. But the return value is not subject to e.g. eval-expression-print-level|length, only its printed value is. As a result, these variables have no effect on eros' overlay display.

A possible fix is to, e.g.:

(let* ((result (eval-last-sexp eval-last-sexp-arg-internal))
	 (print-level eval-expression-print-level)
	 (print-length eval-expression-print-length)
	 (ores (prin1-to-string result t)))
...
  (eros--eval-overlay ores (point))

in eros-eval-last-sexp, and, if a string is passed to eval-overlay, do not format it with %S but use directly:

 (eros--make-result-overlay (if (stringp value) value (format "%S" value)) ...

Happy to submit a PR if you would like.