docu updated

README.md

@@ -1,3 +1,16 @@
-# icinga-checks
+Icinge Check Scripts
+====================
 
 Various check scripts for use in icinga.
+
+All scripts support option `--help`, so call `./scriptname --help` for
+more information.
+
+
+load_per_cpu.sh
+---------------
+
+Icinga plugin to check load average per CPU. Shows 1min, 5min 15min
+average per CPU. Different to check_load, the load is divided by the
+number of CPU units and therefore normalized. So the same warning and
+critical levels fit for any server.