Return rather than exit so as not to block other upgrades

src/freedombone-app-xmpp

         wget $prosody_nightly_url
         if [ ! -f ${INSTALL_DIR}/${prosody_filename}.tar.gz ]; then
             echo $"Failed to download prosody nightly $prosody_nightly_url"
-            exit 345782
+            return
         fi
 
         hash_value=$(sha256sum ${INSTALL_DIR}/${prosody_filename}.tar.gz | awk -F ' ' '{print $1}')
         if [[ "$hash_value" != "$prosody_nightly_hash" ]]; then
             rm ${INSTALL_DIR}/${prosody_filename}.tar.gz
             echo $'Unexpected hash value for prosody nightly download'
-            exit 6824283
+            return
         fi
 
         tar -xzvf ${INSTALL_DIR}/${prosody_filename}.tar.gz
             echo $'Failed to build prosody nightly to /usr/bin'
             rm ${INSTALL_DIR}/${prosody_filename}.tar.gz
             rm -rf ${INSTALL_DIR}/${prosody_filename}
-            exit 3672345
+            return
         fi
         rm ${INSTALL_DIR}/${prosody_filename}.tar.gz
     fi