Add gravity into accele readings

[hanmmmmm]

Hi! Thank you for your awesome work! This pkg works well with the imu. But I noticed that the linear acceleration output in this pkg seems to be the values relative to ground, since the 9.8m/ss gravity in is not present.

Is there any method to put the gravity into the final acceleration output? So when the device is static, the acc are like 0.0, 0.0, 9.8

Thank you!

[maker-ATOM]

Any updates over addition of this feature?