sys, fmt: simplify fmt_s16_dfp, and update documentation

schedstats: revert to 32Bit, and enhance output of schedstats

mrf24j40: Minor cleanup

    - allow formating of val=12345 with fp_digits=6 as 0.012345
    - use assert instead of explicit if
    - remove unused pwr function

drivers/mrf24j40 add tx retries needed get operation

cpu/native: add missing breaks in option parser

cpu/sam0/periph/uart - wake from sleep on receive line

shell/ifconfig: Add STANDBY, print numeric if unknown state

netopt: Add NETOPT_MAC_NO_SLEEP

sys: net: ieee802154: add fallthrough comment

makefile: indentation cleanup

pkg/u8g2: update version

cleanup: remove leftover AUTO_INIT_MODULES

tests/gcoap: Add second listener

make: fix nproc for buildtest

tools: ignore vendor files on whitespace check

SAM3: macro LED0_TOGGLE not working

gcoap: fix resource separator inserting

fmt: Remove unused pwr function