Rover: added RC in/out logging
AP_AHRS: changed default GPS lag to 1 sample

this is based on detailed logs from a LEA-6H and NEO-7N
Rover: split up GPS update into 10Hz and 50Hz parts
Rover: prepare for 2.44 release
AP_NavEKF: added convenient plotting scripts
AP_NavEKF: added pause to gnuplot scripts
AP_NavEKF: added write_flot valgrind functions
AP_NavEKF: removed delay callback
AP_Math: added vectorN class, and index checking
AP_NavEKF: use vectorN to make indexes safe
AP_Math: prevent transpose usage error in matrix API
AP_Math: add const to quaternion API
AP_NavEKF: fixed build for non-Linux
first working GPS fusion