picoC: allowed higher baud rates, bug fix

system.h: allows higher baud rates on USART.
flightbatterystate.h: bug fix at FlightStatusGet()
picoC: change baud rate to unsigned long
picoC: add timeout requester

This adds a time out requester to inform users when a command from gcs
widget fails. This happens when a script is running or the module is
disabled.
picoC: add pathdesired.h and pathstatus.h

This adds access to UAVOs PathDesired and PathStatus. Now picoC can
used for advanced waypoint navigation and autonomous searching tasks.
Just switch to PH, modify the PathDesired object and the Pathfollower
will do the rest.
picoC: add PathDesiredMode

add missing PathDesiredMode value
picoC: small type fix at ChangeBaud()

Changes the LongInteger to UnsignedLongInteger in ChangeBaud()-function.
picoC: add USART functions

Add SendBuffer() and ReceiveBuffer() functions. This makes it possible
to transfer unformatted buffers as fast as possible.
picoC: change return type

changes ReturnValue type from Integer to LongInteger as defined.
picoC: add time() function, USART bugfix

Add a time() function for easier control loops especially PIDs.
USART-functions are now with a functioning timeout parameter. This is a
workaround for defective PIOS-functions.
Merge pull request #1360 from ernieift/ernieift/picoC

picoC: advanced navigation features and bugfixes