refactor: project structure (#9)

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

crates/sysinfo/README.md

@@ -0,0 +1,47 @@
+# System Sensor Provider for asterctl
+
+This tool gathers system sensor values with the help of the [sysinfo](https://github.com/GuillaumeGomez/sysinfo) crate
+and writes them into a text file.
+
+See [README](../../README.md) in root directory for more information.
+
+```
+Proof of concept sensor value collection for the asterctl screen control tool
+
+Usage: sysinfo [OPTIONS]
+
+Options:
+  -o, --out <OUT>
+          Output sensor file
+
+  -t, --temp-dir <TEMP_DIR>
+          Temporary directory for preparing the output sensor file.
+          
+          The system temp directory is used if not specified.
+          The temp directory must be on the same file system for atomic rename operation!
+
+      --console
+          Print values in console
+
+  -r, --refresh <REFRESH>
+          System sensor refresh interval in seconds
+
+      --disk-refresh <DISK_REFRESH>
+          Enable individual disk refresh logic as used in AOOSTAR-X. Refresh interval in seconds
+
+      --smartctl
+          Retrieve drive temperature if `disk-update` option is enabled.
+          
+          Requires smartctl and password-less sudo!
+```
+
+Single test run with printing all sensors in the console:
+```shell
+sysinfo --console
+```
+
+Normal mode providing sensor values for `asterctl` in `/tmp/sensors/sysinfo.txt` every 3 seconds:
+
+```shell
+sysinfo --refresh 3 --out /tmp/sensors/sysinfo.txt
+```