Major g-code parser overhaul. 100%* compliant. Other related updates.

- Completely overhauled the g-code parser. It’s now 100%* compliant. (*
may have some bugs). Being compliant, here are some of the major
differences.

- SMALLER and JUST AS FAST! A number of optimizations were found that
sped things up and allowed for the more thorough error-checking to be
installed without a speed hit. Trimmed a lot of ‘fat’ in the parser and
still was able to make it significantly smaller than it was.

- No default feed rate setting! Removed completely! This doesn’t exist
in the g-code standard. So, it now errors out whenever it’s undefined
for motions that require it (G1/2/3/38.2).

- Any g-code parser error expunges the ENTIRE block. This means all
information is lost and not passed on to the running state. Before some
of the states would remain, which could have led to some problems.

- If the g-code block passes all of the error-checks, the g-code state
is updated and all motions are executed according to the order of
execution.

- Changes in spindle speed, when already running, will update the
output pin accordingly. This fixes a bug, where it wouldn’t update the
speed.

- Update g-code parser error reporting. Errors now return detailed
information of what exact went wrong. The most common errors return a
short text description. For less common errors, the parser reports
‘Invalid gcode ID:20’, where 20 is a error ID. A list of error code IDs
and their descriptions will be documented for user reference elsewhere
to save flash space.

- Other notable changes:

- Added a print integer routine for uint8 variables. This saved
significant flash space by switching from a heavier universal print
integer routine.

- Saved some flash space with our own short hypotenuse calculation

- Some arc computation flash and memory optimizations.

report.h

@@ -22,20 +22,36 @@
 
 // Define Grbl status codes.
 #define STATUS_OK 0
-#define STATUS_BAD_NUMBER_FORMAT 1
-#define STATUS_EXPECTED_COMMAND_LETTER 2
-#define STATUS_UNSUPPORTED_STATEMENT 3
-#define STATUS_ARC_RADIUS_ERROR 4
-#define STATUS_MODAL_GROUP_VIOLATION 5
-#define STATUS_INVALID_STATEMENT 6
-#define STATUS_SETTING_DISABLED 7
-#define STATUS_SETTING_VALUE_NEG 8
-#define STATUS_SETTING_STEP_PULSE_MIN 9
-#define STATUS_SETTING_READ_FAIL 10
-#define STATUS_IDLE_ERROR 11
-#define STATUS_ALARM_LOCK 12
-#define STATUS_SOFT_LIMIT_ERROR 13
-#define STATUS_OVERFLOW 14
+#define STATUS_EXPECTED_COMMAND_LETTER 1
+#define STATUS_BAD_NUMBER_FORMAT 2
+#define STATUS_INVALID_STATEMENT 3
+#define STATUS_NEGATIVE_VALUE 4
+#define STATUS_SETTING_DISABLED 5
+#define STATUS_SETTING_STEP_PULSE_MIN 6
+#define STATUS_SETTING_READ_FAIL 7
+#define STATUS_IDLE_ERROR 8
+#define STATUS_ALARM_LOCK 9
+#define STATUS_SOFT_LIMIT_ERROR 10
+#define STATUS_OVERFLOW 11
+
+#define STATUS_GCODE_UNSUPPORTED_COMMAND 20
+#define STATUS_GCODE_MODAL_GROUP_VIOLATION 21
+#define STATUS_GCODE_UNDEFINED_FEED_RATE 22
+#define STATUS_GCODE_COMMAND_VALUE_NOT_INTEGER 23
+#define STATUS_GCODE_AXIS_COMMAND_CONFLICT 24
+#define STATUS_GCODE_WORD_REPEATED 25
+#define STATUS_GCODE_NO_AXIS_WORDS 26
+#define STATUS_GCODE_INVALID_LINE_NUMBER 27
+#define STATUS_GCODE_VALUE_WORD_MISSING 28
+#define STATUS_GCODE_UNSUPPORTED_COORD_SYS 29
+#define STATUS_GCODE_G53_INVALID_MOTION_MODE 30
+#define STATUS_GCODE_AXIS_WORDS_EXIST 31
+#define STATUS_GCODE_NO_AXIS_WORDS_IN_PLANE 32
+#define STATUS_GCODE_INVALID_TARGET 33
+#define STATUS_GCODE_ARC_RADIUS_ERROR 34
+#define STATUS_GCODE_NO_OFFSETS_IN_PLANE 35
+#define STATUS_GCODE_PROBE_TRIGGERED 36
+#define STATUS_GCODE_UNUSED_WORDS 37
 
 // Define Grbl alarm codes. Less than zero to distinguish alarm error from status error.
 #define ALARM_LIMIT_ERROR -1