Sept.27 Button FB and Motor FB updates

Button FB
LMS has little space so to save string space, event names are repeated 
BUT for the button I can never remember which is a "match" a button and "button changed", so changed to: 

• MATCH/CNF - button, b, pressed matches button pressed
• CHG/IND - button pressed changed (including no button to some button pressed)

Full Tests:

Use a e_cycle every 300ms to check the buttons

Test 1 (works, but..): 

Press button and associated led comes on

Test 2 (works, but..)

- Additonally when Enter pressed, then led comes on and motor moves.

- BUT sometimes when Enter released, led and motor stay on

- 9/29 Buttons are sampled at slower rate than thought so debounce time /counter was too long(1.5sec)/ large (25).   Changed so now works.

Motor FB

• Should a STOP event be added or is it ok to use INIT event to stop a motor?
• Removed BR, brake/coast, flag for L_M_PWR FB.
• Currently the motor is turned on and left on until stopped via INIT event or PWR =0.
• Braking when the motor power > 0, could be damaging to the motors.
• BR flag could be used in a future FB that moves a specific angle