v1.1e: New laser features. G-code parser refactoring. CoreXY homing fix.

- Increment to v1.1e due to new laser features.

- After several discussions with some prominent laser people, a few
tweaks to the new laser mode has been installed.

- LASER: M3 behaves in a constant power mode.

- LASER: M4 behaves in a dynamic power mode, where the laser power is
automatically adjusted based on how fast Grbl is moving relative to the
programmed feed rate. This is the same as the  CONSTANT_POWER_PER_RATE
config.h option in the last version. NOTE: When not in motion in M4,
Grbl automatically turns off the laser. Again, it only operates while
moving!

- LASER: Only G1, G2, and G3 motion modes will turn on the laser. So,
this means that G0, G80 motion modes will always keep the laser
disabled. No matter if M3/M4 are active!

- LASER: A spindle stop override is automatically invoked when a laser
is put in a feed hold. This behavior may be disabled by a config.h
option.

- Lots of little tweaks to the g-code parser to help streamline it a
bit. It should no effect how it operates. Generally just added a parser
flag to track and execute certain scenarios a little more clearly.

- Jog motions now allow line numbers to be passed to it and will be
displayed in the status reports.

- Fixed a CoreXY homing bug.

- Fixed an issue when $13 is changed, WCO isn’t sent immediately.

- Altered how spindle PWM is set in the stepper ISR. Updated on a step
segment basis now. May need to change this back if there are any
oddities from doing this.

- Updated some documentation. Clarified why M0 no longer showing up in
$G and why a `1.` floating point values are shown with no decimals,
like so `1`.

doc/markdown/change_summary.md

@@ -37,6 +37,11 @@ Grbl v1.1's interface protocol has been tweaked in the attempt to make GUI devel
 
 In addition, all `$x=val` settings, `error:`, and `ALARM:` messages no longer contain human-readable strings, but rather codes that are defined in other documents. The `$` help message is also reduced to just showing the available commands. Doing this saves incredible amounts of flash space. Otherwise, the new overrides features would not have fit.
 
+Other minor changes and bug fixes that may effect GUI parsing include:
+
+- Floating point values printed with zero precision do not show a decimal, or look like an integer. This includes spindle speed RPM and feed rate in mm mode.
+- `$G` reports fixed a long time bug with program modal state. It always showed `M0` program pause when running. Now during a normal program run, no program modal state is given until an `M0`, `M2`, or `M30` is active and then the appropriate state will be shown.
+
 On a final note, these interface tweaks came about out of necessity, because more data is being sent back from Grbl, it is capable of doing many more things, and flash space is at a premium. It's not intended to be altered again in the near future, if at all. This is likely the only and last major change to this. If you have any comments or suggestions before Grbl v1.1 goes to master, please do immediately so we can all vet the new alteration before its installed.
 
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