Tracker: Kinetis development board support

[jnohlgard]

This is a tracker issue for tracking the progress of adding more NXP Kinetis Freedom development boards to RIOT.

http://www.nxp.com/products/software-and-tools/hardware-development-tools/freedom-development-boards:FREDEVPLA

#	Board	MCU family	CPU core	Status	Documentation	Key features
1	FRDM-K64F	K64F	K, M4F	supported	documented	Ethernet, USB, FXOS8700CQ accelerometer+magnetometer, SDHC
2	FRDM-K22F	K22F	K, M4F	supported	no wiki	USB, FXOS8700CQ accelerometer+magnetometer
3	FRDM-KW41Z	KW41Z	KL, M0+	supported	no wiki	802.15.4 and BLE combined radio, FXOS8700CQ accelerometer+magnetometer
4	FRDM-KL43Z	KL43Z	KL, M0+	#9012	no wiki	USB, segment LCD, MMA8451Q accelerometer, MAG3110 magnetometer
5	USB-KW41Z	KW41Z	KL, M0+	todo	no wiki	USB dongle form factor, useful for running a border router
...	FRDM-K28F	K28F	K, M4F	todo	no wiki	1 MB RAM, USB, 16 MB external SDRAM, 32 MB NOR SPI Flash
...	FRDM-KL25Z	KL25Z	KL, M0+	to do	no wiki	low cost (13 EUR) dev board, USB, MMA8451Q accelerometer
...	FRDM-KL27Z	KL27Z	KL, M0+	to do	no wiki	USB, MMA8451Q accelerometer, MAG3110 magnetometer, thermistor

[stale]

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