* Support for multiple Max7219 units in a chain
I'll move this support over to bugfix_2.0.0 in the next few days. And
then look at updating the Max7219_idle() routine to make use of multiple
units in a chain.
* spelling correction
* Initial conflict resolution
All previous items resolved:
- Use of ELAPSED() on timer code
- Switch to use of defer_return_to_status=true as much as possible
- Update & Clean Up of Max7219 routines
* Resolve non-SD case in ultralcd.cpp
* Add MAX7219_DEBUG to Travis CI testing
* Tweak config and use standard pin naming for MAX7219_DEBUG
* MAX7219: Apply coding standards, use macros, etc.
* Make code work...
* Add Max7219 LED Matrix Debug Support
The Max7219 8x8 LED Matrix's are very helpful for debugging new code.
And for that matter, just trying to maximize printer settings without
causing stuttering.
The displays are very inexpensive (under $2.00 with shipping) and
provide a lot of help when trying to debug complicated code.
* Try to keep Makefile up to date.
