Merge "- creates proper ifc.h and dhcp.h headers for libnetutils - adds...

Merge "- creates proper ifc.h and dhcp.h headers for libnetutils - adds ifc_set_hwaddr - adds hwaddr command to netcfg - code reuse: dhcp_configure calls ifc_configure; inet_ntoa is used for printing - consistency: use net.XXX.dnsX properties in favor of dhcp.XXX.dnsX properties   (see related change to WifiStateTracker) - updated system/core/nexus to use new headers, although not sure if anybody still uses nexus"