allow creation of different kind (java, python, etc) (#44)

diff --git a/lib/actions.js b/lib/actions.js
index 0348b70..75942af 100644
--- a/lib/actions.js
+++ b/lib/actions.js
@@ -38,8 +38,7 @@
     if (!options.hasOwnProperty('action')) {
       throw new Error(messages.MISSING_ACTION_BODY_ERROR)
     }
-
-    const body = { exec: { kind: 'nodejs:default', code: options.action } }
+    const body = { exec: { kind: options.kind || 'nodejs:default', code: options.action } }
 
     if (options.action instanceof Buffer) {
       body.exec.code = options.action.toString('base64')