Add changes to .gitignore file

.gitignore

@@ -16,6 +16,11 @@
 npm-debug.log*
 yarn-error.log
 testem.log
+package-lock.json
+
+# terraform state handling
+cloud/terraform/terraform.tfstate
+cloud/terraform/terraform.tfstate.backup
 
 # ember-try
 .node_modules.ember-try/