Move components into dedicated subdirectory

This brings us a lot more tidiness.

components/temperature.c

@@ -0,0 +1,13 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+
+#include "../util.h"
+
+const char *
+temp(const char *file)
+{
+	int temp;
+
+	return (pscanf(file, "%d", &temp) == 1) ?
+	       bprintf("%d", temp / 1000) : NULL;
+}