xtables-addons: update to v2.1, fix compilation against Linux 3.7.2, refresh patches

git-svn-id: svn://svn.openwrt.org/openwrt@35192 3c298f89-4303-0410-b956-a3cf2f4a3e73
xtables-addons: move to package/, add myself as maintainer


git-svn-id: svn://svn.openwrt.org/openwrt@35193 3c298f89-4303-0410-b956-a3cf2f4a3e73