CMakeLists file missing for support of ROS and nodes to be added

Currently this library does not include the 'CMakeLists.txt' file required to support its use within ROS. Therefore when implemented as such it will need to be added manually.
This should be included within this library and configured for zz__MiRaspbPi__zz

Also want to increase the functionality of the repository such that there are nodes for each of the classes, such that it is 'easy' to create the hardware layer for a ROS package.

Tasks

• Investigate into options for how nodes can be configured for multiple instances
• Setup the service server such that it has a queue for 1 instance at a time
  • ros::spin() to be used, so that each hardware node has a single instance + will not work in parallel
  • Can't seem to find a way to specify a callback queue size, however this are options for multiple callback queues (however, as want to have the hardware nodes only take 1 action at a time, this isn't needed)
• Understand parameters
  • For private parameters a seperate 'NodeHandle' is to be created
• Launch node with argument inputs?
  • Easy enough to do, either use or
• Can the YAML be used to configure roslaunches?
  • The yaml file might get a bit busy, but can be used to provide rosparams for node generation
• Node log files to be copied to a local location if/when nodes closed
• GPIO node to be created (v0.2.2)
• USART node to be created (v0.2.2)
• SPI node to be created (v0.2.2)
• I2C node to be created
• #16
• #17

Start by reviewing the repository structure and the requested CMakeLists.txt integration for ROS and zz__MiRaspbPi__zz. Then scope the remaining node work, including log-file handling and the GPIO, USART, SPI, and I2C nodes. Done means the library can be used in ROS without manually adding CMake configuration and the listed nodes are implemented.