update for libgadu
- Update to version 1.11.4, bugfix release:
+ Fix buffer overflow with remote code execution potential.
Only triggerable by a Gadu-Gadu server or a man-in-the-middle.
CVE-2013-6487 (bnc#861019, bnc#878540)
+ Fix memory overwrite in file transfer with proxy server.
CVE-2014-3775 (bnc#878540)
+ Minor fixes reported by Pidgin project members.
- Submitted by Stanislav Brabec (sbrabec)