Servo8Bit & Arduino 1.6.9

[hreintke]

@fri000 :
I recently started to use Servo8Bit on an attiny85, together with Arduino 1.6.9.
In order to get it to work I needed to make some fundamental/hackish updates to the library.

Are you still active with this library ?

If so, I will make a detailed issue with config & updates I made, so we can see whether this is caused by my misunderstanding or a misalignment between the Arduino & servo8Bit librarries.

[maltevonehren]

I found the Issue was a simple c++ problem in the Servo8Bit constructor. For some reason after the constructor myServoNumber is 0 instead of invalidServoNumber. This results in the register function not being called and nothing happening. Changing the default for myServoNumber to ServoSequencer::kInvalidServoIndex instead of invalidServoNumber fixes the problem.

[FedericoBusero]

See #9