Allow pause during manipulator home.

System returns to waiting for enable if any of the homing routines
are interrupted by the pause state
Homing changes in master executive.
Start action server and services after smach.
New manipulator action for homing or grab.

This will allow us to use a single action server in manipulator node.
Moved dynamixel position mode weirdness handling.

This class now disables feedback polling any time it's dynamixel is
transitioned from wheel mode to position mode.
Consolidated manipulator action servers.

The manipulator node now has one action server.  It wraps the state
machine, and with the 'type' field, allows a client to grab samples
or to home the manipulator.
Removed dynamixel position mode handling.

This is now moved to joint_controller_mx.py
Wait for all pause services before reading GPIO.
Modfied action client for new manip. homing.
Removed unneeded delay.
Always start paused.  Initial GPIO = paused.
Return preempted if paused during home.

State machine waits for unpause if paused during grab action still.
During homing, it return preempted to the executive.
Merge branch 'homing'