Global code ovehaul - remove CAS and other, add 15 minute greet check

- Remove CAS, as it no longer works for us
- Remove other checks
- Implement 15 minute greet timeout check
- Fix chat logos
- Ditch thirdparty logger, use stdlib log facility wrapper for logging

internal/moon/exitCode_windows.go

@@ -0,0 +1,18 @@
+//go:build windows
+
+package moon
+
+import "os"
+
+// exitCodeFor maps one terminating signal to the status a stopped process
+// should carry. Windows has no signal numbers to follow, so it imitates the
+// Unix convention: Ctrl+C is an interrupt, and an interrupt is 130.
+func exitCodeFor(s os.Signal) int {
+	if s == os.Interrupt {
+		return signalExitBase + 2
+	}
+
+	return 0
+}
+
+/* vim: set ft=go noet ai ts=4 sw=4 sts=4: */