[packages] update strongwan to version 5.0.1.

Added plugin, new in 5.0.1:
* unity - Cisco Unity extension

Removed plugin not available in 5.0.1:
* socket-raw - raw socket implementation for charon

Signed-off-by: Mikael Magnusson <mikma@users.sourceforge.net>

git-svn-id: svn://svn.openwrt.org/openwrt/packages@35006 3c298f89-4303-0410-b956-a3cf2f4a3e73