- Allow planner to alter the deceleration phase of the currently executing block.
- Remove BUSY flag, as it is NON ATOMIC to set bits in the Stepper ISR and Planner at the same time.

Fixed for cycle used to initialize default values

...and recommended pulse width configuration for A4988

Co-Authored-By: p3p <p3p@p3psoft.co.uk>

* Planner: Removal of some race conditions between Stepper ISR and Planner, some of them pointed out by @AnHardt, some of my own findings
* Fixing timing on stepper pulses adding a compensation for the non-null time required to set ports.

According to https://github.com/MarlinFirmware/Marlin/issues/9917#issuecomment-399204568

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