Blocked message sending to ended tasks.
Modified lte-softmodem to use ITTI signal handling.
Uniformized lte-softmodem and oaisim with ITTI handling.

git-svn-id: http://svn.eurecom.fr/openair4G/trunk@4607 818b1a75-f10b-46b9-bf7c-635c3b92a50f