Made IOBundle extend AutoCloseable

Made IOBundle extend AutoCloseable to make it easy to pass around IOBundle instances that can be closed.

ModbusSlave -> ModbusSlaveBus and added ModbusSlave

ModbusSlave -> ModbusSlaveBus and added ModbusSlave.

You can now use ModbusSlave to communicate with a specific Slave without specifying the address. That is now the job of the implementation.

Signed data types bug fixes

Signed data types bug fixes.

Easily read and write values to and from a modbus slave

Easily read and write values to and from a modbus slave.

First release!

The first release!