1) Break out of email_send_all if one is failing to send email and more then 5 seconds have elapsed.
2) Get queued emails in reverse order - i.e. try to send new emails first before failing emails.

git-svn-id: http://mantisbt.svn.sourceforge.net/svnroot/mantisbt/trunk@4464 <a class="text" href="/?p=mantisbt.git;a=object;h=f5dc347c">f5dc347c</a>-c33d-0410-90a0-b07cc1902cb9