minor cleanup LCD_I2C example
add correlationid to OneWire read- request and reply
for backwards compatibility support correlationid in protocol version > 2.4 only
permit digital_write for pins configured as input (to switch on internal pullups)
change semantics of is_configured_mode and is_supported_mode to not die but return undef. Fix missing 7-bit translation in digital_write
merge changes from dev
fix handle onewire in capability-response