unittests/littlefs: fix unittests

Dummy RAM mtd was too small to run unit tests correctly.
Added some sectors and reduced page size.

gnrc_ipv6_nib: fix final RA behavior

This fix

* assures that the periodicity of the final router advertisements is
  kept (so that no administrative change e.g. adding prefixes to the
  prefix list causes additional RAs outside the rate limitation)
* removes all administrative options (PIO, ABRO, 6CO) from final router
  advertisements (with router lifetime == 0)

boards/arduino-mkrfox1200: add board configuration for ata8520e

drivers/ata8520e: add initial implementation (without netdev but provides Sigfox feature)

boards/arduino-mkrfox1200: add initial implementation (without SigFox)

drivers/enc28j60: Add feature deps to makefile

boards: cleanup structure of wsn430 boards

boards/nucleo: share board.h and board.c

boards/*: make doxygen brief description consistent

drivers/tja1042: move to drivers_can group

gnrc_netif: remove "new" qualifier in documentation

Calling the API "new" when it is the only network interface API (that
also now is named the same as the old one) might be a little confusing.

pkg/relic: disable newline-eof compile error

gnrc_netif: set-up 6Lo for NRFmin

cpu/native/socket_zep: fix doxygen grouping

ci: murdock: print worker information for static tests

pkg/libcoap: update patches for git >=2.15.x

socket_zep: remove unnecessary include