refactor: project structure (#9)

Split up project into multiple crates and use a Cargo workspace.

docs/shell_commands.md

@@ -0,0 +1,27 @@
+# Linux Shell Control Commands
+
+Turning the display on or off is possible directly in a Linux shell!
+
+Add your user to the `dialout` group for access to `/dev/ttyACM0`:
+
+```shell
+sudo usermod -a -G dialout $USER
+```
+
+> You may have to log out and back in for group changes to take effect.  
+> If not using a Debian based Linux, the tty device might have a different name, or not using the `dialout` group.
+
+
+## Turn display on
+
+```shell
+stty -F /dev/ttyACM0 raw
+printf "\252U\252U\v\0\0\0" > /dev/ttyACM0
+```
+
+## Turn display off
+
+```shell
+stty -F /dev/ttyACM0 raw
+printf "\252U\252U\12\0\0\0" > /dev/ttyACM0
+```