Default to ThrottleModeDownZero

When starting up, if you start the GS before connecting the bluetooth joystick the QGC needs to be closed and restarted to get it to recognize the joystick

Add note about button bits

This reverts commit c01ceadd.

Don't send button pressed bits to MANUAL_CONTROL

Remove deprecated button count testing

Remove the concept of reserved buttons for manual control

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Some digital joysticks have already this correction
Add habilit to add or removecircle correction
Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Joystick axes and buttons can now be monitored even when the
joystick input is disabled.

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Revert "Removed code that cut off the last 25% of joystick motion in either direction. I'm not sure what the original purpose of this code was."

This reverts commit 4c34fb38.

Changed Joystick._exponential from bool to float. It can now be set between 0 and -0.5 by user using a slider.

Sensitivity of axis increases and deadband increases. This fixes an issue where the maximum percent output from an axis would be 100% - percentDeadband.

Removed code that cut off the last 25% of joystick motion in either direction. I'm not sure what the original purpose of this code was.