Fix a bug in read-list involving whitespace before a ')'
Fix a bug in read-list involving whitespace before a ')'

Previously all we did to check for the end of the list was check if the
very first character after reading the previous sexpr is ')'. This means
that the reader would hang forever when given something like '(1 2 3 )'

orodley/nucleus,orodley/nucleus,orodley/nucleus