libs/json: add proper support for decoding unicode escapes

git-svn-id: http://svn.luci.subsignal.org/luci/trunk@9935 ab181a69-ba2e-0410-a84d-ff88ab4c47bc
libs/core: make luci.model.network compatible with new wireless netifd integration

git-svn-id: http://svn.luci.subsignal.org/luci/trunk@9936 ab181a69-ba2e-0410-a84d-ff88ab4c47bc