See https://github.com/MarlinFirmware/Marlin/issues/5597#issuecomment-397683325

The registers within the Max7219 can get corrupted a number of ways.  This allows the Max7219 to be reset and fully initialized.
And...  it also allows the user to see the initialization pattern.

Fix message to long for 12864 display

Added reset bltouch instead. This ensure properly stow even when in error.

Fix #8890

Always honor minimum period on stepper pulse generation, and fix timing calculations

Signed-off-by: etagle <ejtagle@hotmail.com>

- Drop `max_jerk` with `JUNCTION_DEVIATION`
- Add `max_e_jerk_factor` for use by `LIN_ADVANCE`
- Recalculate `max_e_jerk_factor` when `junction_deviation_mm` changes
- Fix LCD editing of `junction_deviation_mm`

- Enable / disable interrupts with `__iSeiRetVal` / `__iCliRetVal`
- Add STM32F1 to Travis CI tests

An undocumented hw bug makes the UART lose chars when RX ISR is disabled, even for a very small amount of time. This happens when RX_BUFFER > 256, and the result is corrupted received commands. Solved by implementing pseudo-atomic operations on 16bit indices.

The timing value should be properly set for ALL boards. The compiler will check and set maximum step rate calculations based on those values.

- Stepper bugs fixed
- Support MIXING_EXTRUDER with Linear Advance
- Miscellaneous cleanup

Pointed out by @GMagician