[packages] strongswan: upgrade to 5.0.4

git-svn-id: svn://svn.openwrt.org/openwrt/packages@36649 3c298f89-4303-0410-b956-a3cf2f4a3e73
[package] lxc: add new package

git-svn-id: svn://svn.openwrt.org/openwrt/packages@36651 3c298f89-4303-0410-b956-a3cf2f4a3e73