Add shebang to examples

examples/basic/02_FixLogGrep/FixLogGrep.pow

@@ -1,3 +1,5 @@
+#!/bin/sh
+
 kapow route add /apache-errors - <<-'EOF'
 	cat /var/log/apache2/access.log | grep 'File does not exist' | kapow set /response/body
 EOF