PiOS M5611: Create task which does nothing
PIOS MS5611: Move getting the data and the calculation of pressure
into the driver task

https://github.com/PhoenixPilot/PhoenixPilot/issues/153
PIOS MS5611: Use a dynamically allocated device structure instead of lots
variables on the stack

https://github.com/PhoenixPilot/PhoenixPilot/issues/153
PiOS MS5611: Get rid of lots of camel case

https://github.com/PhoenixPilot/PhoenixPilot/issues/153
PIOS MS5611: Move the temperature interleaving setting into the
device configuration.  If not specified it will default to 1.

https://github.com/PhoenixPilot/PhoenixPilot/issues/153
Sensors task: Move getting the baro data from the baro queue
to this module

https://github.com/PhoenixPilot/PhoenixPilot/issues/153

Note: The old altitude module is being deleted here with some sonar code
so if you are trying to get the data from PIOS_HCSR04 that should be
modified to a driver with a task as well.
PiOS MS5611: Small fixes
PiOS MS5611: Fixes from Stac's comments
PiOS MS5611: More comments
PiOS MS5611: Some more small fixes
Merge branch 'next' into ms5611
PIOS MS5611: Fix bug that was causing this to saturate the baro queue
Merge pull request #160 from peabody124/ms5611

Make the ms5611 driver have an internal task