G-Sync Highlighting M00/M01

[dkhughes]

Related to #162, highlighting of a pause command in the code viewer is not functioning as expected. When the control is paused, the gsync update line function is not being called for the M00 command in the following stub program:

G17 G20 G90 G40 G54

#<count>=0.0
o100 do
(Simulate a M00 condition)
(like a manual tool change op.)
G01 X5.0 Y5.0 F150.
M00 (Wait on operator)
G01 X0. Y0.0
#<count> = [#<count> + 1.];
o100 while[#<count> LT 10.]

G40 G1 X0.0 F100.

M02

This causes some visual confusion when the GUI buttons enter pause state, but the M00/M01 command is not highlighted as the active line of code.

I'm not sure yet if this is underlying in machinekit, or if the gsync module should hook an event besides just motion updates.