Fix import of text files into ZODB.

When importing back ace.js containing a last line with whitespaces only, the
last line was not imported, and thus the file could never been downloaded
completely as its really size was less than the one on the File ZODB object.
Cosmetic: Remove unused variable.
Fix legacy jQuery.ajax() success function being called but HTTP connection is refused.

http://bugs.jquery.com/attachment/ticket/5968/0001-Fix-jQuery.ajax-success-function-being-called-when-H.patch