[gpio] Changes the gpio_set_pin_mode_output call

Now requires an output value. Thus, the state of the pin
will be known by the developper (avoid avoid burning things :D)
Updates changelog
[pwm] Do not start the PWM timer by setting period

This allow the pwm to be fully configured in initialization phase before
being run. Adds new start/stop/reset function
Updates version number
Merge branch 'release/0.10a' into develop