- Fixed bug (noted in svn 5275) that could cause read_sexpr_block to   hang if the file ended mid-sexpr, or ended with a non-paren sexpr   with no trailing whitespace.
- Fixed bug (noted in svn 5275) that could cause read_sexpr_block to
  hang if the file ended mid-sexpr, or ended with a non-paren sexpr
  with no trailing whitespace.

svn/trunk@5277

nltk/nltk,nltk/nltk,nltk/nltk