add monit example

examples/monitrc.conf

@@ -0,0 +1,6 @@
+check process crono_myapp
+  with pidfile /path/to/crono.pid
+  start program = "bundle exec crono" with timeout 30 seconds
+  stop program = "kill -s TERM `cat /path/to/crono.pid`" with timeout 30 seconds
+  if totalmem is greater than 500 MB for 2 cycles then restart
+  group myapp_crono