Fix 0003728: CSV export shows " instead of real quotes in bug title.

M csv_export.php

• The main bug was fixed in the re-implementation of the csv export done earlier.
• This commit fixes the error "SYLK: invalid file format" error that used to be prompted by Excel.

git-svn-id: http://mantisbt.svn.sourceforge.net/svnroot/mantisbt/trunk@2482 <a class="text" href="/?p=mantisbt.git;a=object;h=f5dc347c">f5dc347c</a>-c33d-0410-90a0-b07cc1902cb9