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/jogging.md

@@ -13,7 +13,8 @@ Executing a jog requires a specific command structure, as described below:
    - G20 or G21 - Inch and millimeter mode
    - G90 or G91 - Absolute and incremental distances
    - G53 - Move in machine coordinates
- - All other g-codes, m-codes, and value words are not accepted in the jog command.
+   - N line numbers are valid. Will show in reports, if enabled, but is otherwise ignored.
+ - All other g-codes, m-codes, and value words (including S and T) are not accepted in the jog command.
  - Spaces and comments are allowed in the command. These are removed by the pre-parser.
 
  - Example: G21 and G90 are active modal states prior to jogging. These are sequential commands.