Increment to v1.1a, minor compile bug fix, tweaked communication protocol, more docs.

- Incremented to v1.1a, rather than keep 1.0e. This is because there
are existing v1.0 installations. Don’t want to confuse people further.

- Certain version of the Arduino IDE did not like the `inline` in the
function header. Removed from spindle_control files to fix the problem.

- Tweaked the communication protocol slightly. Added message type
indicators for all `[]`bracketed feedback messages. It’s been
problematic for GUI dev to try to determine the context of a message
and how it should be handled. These indictors should help tremendously
to remove context all together.

- Also altered how `$N` startup lines are presented when executed. They
now start with an open chevron ‘>’ followed by the line and an ‘:ok’ to
indicate it executed. The ‘ok’ is on the same line intentionally so it
doesn’t mess up a streaming protocol counter.

- Managed to save a 100+KB from refactoring parts of report.c. (Thanks
Vasilis!) Freed up room to alter the protocol a little.

- Wrote a markdown document on interface messaging to make it clear how
it’s intended to work. See interface.md in /doc/markdown

- Started to pull in some Wiki pages from the old grbl site and
beginning to update them for v1.1.

- Created new commit log for v1.1.

grbl/report.h

@@ -114,8 +114,9 @@ void report_ngc_parameters();
 // Prints current g-code parser mode state
 void report_gcode_modes();
 
-// Prints startup line
+// Prints startup line when requested and executed.
 void report_startup_line(uint8_t n, char *line);
+void report_execute_startup_message(char *line, uint8_t status_code);
 
 // Prints build info and user info
 void report_build_info(char *line);