Updated flexiforce resources for response consistency when observing vs when using normal GET.

Changed threshold for living flexiforce sensor.
Added push based discovery for every sensor, also added a bash script to flash the nodes.

Note that the kitchen-server node crashes when using a msp430-gcc compiler newer than 4.5.
Merge branch 'coap13' of https://github.com/fvdnabee/contiki-sensinode into coap13