* 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!

Also...   Doing a 'Direct Commit' to see if that is 'acceptable' for small changes like this.   I want to look at the commit history and see how the logs handle this type of change.

Thank You MagoKimbra !

* Fix thermal protection documentation.

Even before the recent thermal protection changes, the documentation of
the thermal protection feature in the config files did not match the
implementation.  I fixed the documentation and reconciled the M303
implementation with the documentation.

* Applied documentation changes to sample config files

* Renamed hysteresis to watch_temp_increase

* Added gcodes back into documentation.

If #define MSG_Z_FADE_HEIGHT is xx.xx then the last character is crashing into the value