Fix compilation issues for json and xml resources
Fix coap xml format
Fix parent field in udp-client for ndp mode
Use proper event to restart 6lbr
Define stdint printf macros if they are not defined
Improve Econotag traces
Add nvm proxy application and scripts
Add UIP_CONF_ND6_SEND_NA to contiki-default-conf.h
Disable IPv6 Neighbor Discovery Protocol by default on the sky platform