Change SendImage() to output a more consistent status variable.

(closes issue #13134)
 Reported by: eliel
 Patches: 
       app_image.c.patch uploaded by eliel (license 64)
       UPGRADE.patch uploaded by eliel (license 64)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@134088 65c4cc65-6c06-0410-ace0-fbb531ad65f3