support for on()/off() in LCD

Support to switch on and off the LCD.

{{{

!c++

void on() { display(); backlight(); } void off() { noBacklight(); noDisplay(); } }}}

Closes #20 - remove wait 1us during interrupt masking in loadSR. Not needed. Closes #19 - Added support for on/off commands Closes #18 - Set backlight initial state during initialization to off. Closes #17 - New SR3W class. Added documentation for new class Move some methods for the public interface of the LCD class to private, since they should never be called by the user.

→ c5879ff3f2e5