We have data! (sort of)

Things achieved today:
- Moved random functions into a tools module, hence no need for a
"main.h"
- Currently RPi port forced at 9001 (it's over....) to get data to send
- Receiving some data from the GUI! Not all of it sadly...
- Added user option to choose port used

Things to do:
- Automatically find port
- Get the RPi to read all of the data instead of for some reason only
the first 4 bytes
- Get the RPi to read multiple sends instead of quitting after receiving
one message
- RPi to send it's (currently hardcoded) response