Fix #111, error with docstrings containing single quotes
ESCAPE-STRING assumes the resulting string is going to be double-quoted,
and LAMBA-NAME/DOCSTRING-WRAPPER was only single quoting them.

A similar issue was present for function names with single quotes. These
should be read differently, i.e. FO'O => FO (QUOTE O), but until the
reader is fixed to deal with this I think allowing them in function
names makes more sense than failing with a strange error message
Merge pull request #113 from orodley/quotes-in-docstrings

Fix #111, error with docstrings containing single quotes