Added a custom home position for checking the joints offsets calibration

[nunoguedelha]

Added a custom home position for checking the joints offsets. The chosen reference joint positions are:

• legs: all set to 0 except hip roll and ankle roll respectively set to 10, -10
• torso: all set to 0
• arms: set as per the ArmFineCalibration wiki.

For using these settings, select [customPosition_CheckJointCalibration] among the custom positions.