Add shebang to examples

examples/basic/01_HelloWorld/HelloWorld.pow

@@ -1 +1,3 @@
+#!/bin/sh
+
 kapow route add /helloworld -c "echo 'Hello World!' | kapow set /response/body"

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

examples/basic/03_DynamicLogGrep/DynamicLogGrep.pow

@@ -1,3 +1,5 @@
+#!/bin/sh
+
 kapow route add /apache-logs - <<-'EOF'
 	cat /var/log/apache2/access.log | grep -- "$(kapow get /request/params/pattern)" | kapow set /response/body
 EOF

examples/basic/04_SystemMonitor/SystemMonitor.pow

@@ -1,3 +1,5 @@
+#!/bin/sh
+
 kapow route add '/file/{path:.*}' -c 'ls -la -- "/$(kapow get /request/matches/path)" | kapow set /response/body'
 
 kapow route add /process -c 'ps -aux | kapow set /response/body'