Plane: added FS_LONG_TIMEOUT and FS_SHORT_TIMEOUT parameters

this is to address the issue raised here:

http://diydrones.com/forum/topics/ardupilot-circle-mode
RC: set dead zone only if parameter has not been set by user
Plane: set_dead_zone renamed to set_default_dead_zone

Change in use of parameter means value passed in should be 1/2 what it
was previously
Rover: set_dead_zone renamed to set_default_dead_zone

Change in use of parameter means value passed in should be 1/2 what it
was previously
Copter: set_dead_zone renamed to set_default_dead_zone

Dead zones now set as part of rc initialisation instead of only after
eeprom is erased.
Change in use of parameter means value passed in should be 1/2 what it
was previously
RC: example sketch uses set_default_dead_zone
AP_TECS: compile error fix for size_of(log_tuning)
Plane: fixed handling of deadzone in ACRO mode

RC_Channel norm_input() does not take account of the dead zone
Plane: fixed a bug with altitude drift in FBWB mode

not taking account of deadzone correctly
Copter: cli to report ch8 radio values
attempt to change from 1/10th second to 2/10th second on flight mode switch
Copter: comment fix for flight mode switch delay const
Copter: remove param to disable accel based throttle controller