rewrote mpu6050 revision sensing code to match that of eMPL from Invensense.
Also changed scalefactor for acc to 256/512 to match multiwii code. untested/etc, proceed with caution.

git-svn-id: https://afrodevices.googlecode.com/svn/trunk/baseflight@276 7c89a4a9-59b9-e629-4cfe-3a2d53b20e61
removed mpu6050_scale cli since it's now autodetected.
the value is now printed in the status command, after MPU6050 as MPU6050.n = new revision, MPU6050.o = old revision.

git-svn-id: https://afrodevices.googlecode.com/svn/trunk/baseflight@278 7c89a4a9-59b9-e629-4cfe-3a2d53b20e61
reversed o/n meaning from previous commit to actually mean what I said :)
n = new rev (fullscale acc)
o = old rev (halfscale acc)


git-svn-id: https://afrodevices.googlecode.com/svn/trunk/baseflight@279 7c89a4a9-59b9-e629-4cfe-3a2d53b20e61