Z_PROBE_REPEATABILITY test

Z_PROBE_REPEATABILITY test for Auto Bed Leveling.
Implemented as M48 with extra user specified options.
Full support at
http://3dprintboard.com/showthread.php?2802-Auto_Bed_Leveling-Z-Probe-Repeatability-code

(cherry picked from commit 009186558314b942b0dd1b968eca6a777337b3e1)
Fix Default Configuration so Auto Bed Leveling is off

This snapshot has the Auto Bed Leveling turned off because most Marlin
users do not have that feature.

(cherry picked from commit 0adbc79571e7aef39378b1c0c59b5cbaa5b1a3a3)