fix ahrs_is_aligned()
renamed AUTOPILOT_ARMING_x to USE_x_FOR_MOTOR_ARMING
removed battery_buzzer module, replaced by the more generic bat_checker module
a little rotorcraft airframe cleaning
Merge pull request #174 from flixr/rotorcraft_arming

* never start the motors if AHRS is not aligned (disable it with AUTOPILOT_DISABLE_AHRS_KILL)
* if USE_KILL_SWITCH_FOR_MOTOR_ARMING is defined (to 1):
  * switch kill switch off to arm the motors
  * if kill switch is off during startup, you need to kill again first, then unkill to start
  * throttle needs to be down, other sticks centered to start motors
  * need to be in manual mode to start the motors
* if USE_THROTTLE_FOR_MOTOR_ARMING is defined (to 1):
  * automatically start motors when applying throttle
  * if throttle was not down at startup, you need to put throttle down again first
  * other sticks need to be centered to start motors
  * need to be in manual mode to start the motors
* else the "default" arming sequence with the yaw-stick-to-the-corner is used
* if you have a RADIO_KILL_SWITCH defined, it it will be used to go into kill mode, regardless of what motor arming option is used
Merge pull request #177 from flixr/rotorcraft_nominal_throttle

Easier setting of a fixed nominal throttle command if one doesn't want to use the adaptive vertical filter.
Define GUIDANCE_V_NOMINAL_HOVER_THROTTLE (in percent), otherwise the adaptive hover is used.
You can also use settings to tune it.
Merge branch 'dev' into 4.0_beta

* rotorcrafts: additional motor arming options: #174
* rotorcrafts: easier setting/tuning of nominal hover throttle if adaptive filter is not used: #177
* rotorcrafts: some more fixed when changing vertical guidance modes
* bat_checker module
* updated some ADC stuff for lisa/m: #159
  You should now be able to use ADC_1, ADC_2, ADC_3 for the ADCs on the ANALOG1
no trailing whitespaces please
updated the hardware test airframe files, positive gains, etc.
wrap define of ABS in ifndef in std.h
print period and freq of modules' periodic functions

in generated/modules, define freq/period with
the name of the function all in capital letters
followed by _FREQ or _PERIOD
use new generated x_PERIODIC_FREQ in bat_checker module
Merge branch 'master' into dev

* print period and freq of modules' periodic functions
* updated bat_checker module to use that
no arms aspirin2 gyro acc sings and calibrated. MAG not yet
quat quat motors on first time note tuned
NOARMS FISRT flight
Added preliminary support for luftboot.

By default all lisa/m 2.0 firmware will end up at address 0x8002000 and
jtag will put it there without erasing the bootloader. If you intend to
not use Luftboot you have to set
<configure name="NO_LUFTBOOT" value="1"/>
in your airframe file.

Using DFU for flashing firmware still needs to be added.
Added the dfu flashing script. Lisa/m 2.0 board is now by default using the DFU flashing mode.

As paparazzi (payload) does not contain a way to switch to the
bootloader yet you need to connect ADC2 pin to ground on power up to
force the bootloader mode.
call mag handler in imu aspirin2 driver, otherwise will never be scaled
Lisa/L does not use luftboot. Make it so! :)