Implemented synchronization message output for NanoDLP printers (nanodlp.com).
If optional feature is enabled in `Configuration_adv.h`, Marlin will ouput "Z_move_comp" string to serial after completing any G0/G1 Z-axis movements. This feature patched on previous versions(1.0) is used by NanoDLP to synchronize Z-axis movement with projector exposure in DLP stereolithography printers.

Example Configuration.h files are not updated yet.   You need to cross
your settings over to the default Configuration.h file in the \Marlin
directory.   (UBL_G26_MESH_VALIDATION enablement has moved to a new
location in the file.)

For parity with bugfix-2.0.x

Just aligned with version 2.0. Here bug was not present

Followup to 13a3fb1acc

This PR will address two issues reported in #8492. Just one is left because I don't know if it is an issue or not

1) when no home is done ("no_move" is set) tool change should never move X & Y because... I don't know where I am...only Z should be adjusted to avoid bed collision if other nozzle is lower than current.
2) Since no move no bed level matrix should be applied
    When SWITCHING_NOZZLE is enabled and system is homed there are two movements to go to destination, but first can move Z to older position and then crash on the bed

This is a non-intuitive change.   @oldmcg says in this post https://github.com/MarlinFirmware/Marlin/issues/7572#issuecomment-340641207 that using DELTA_PRINTABLE_RADIUS is better than DELTA_PROBABLE_RADIUS for setting the probe limits.   This is because the automatic probe code checks all locations for being reachable by the probe prior to doing the probe.

Fixes #7978

* Fix up Travis CI and compile warnings/errors

* No ULTRA_LCD with REPRAP_DISCOUNT_SMART_CONTROLLER

* No point in setting all the endstop plugs

This fixes the old implementation of M428 which was broken, did not
match the website, and made no sense.

Thanks @RowanMeara!