better build placeholder errors. closes #13

Author: olov

build/es5/ng-annotate

@@ -1,3 +1,3 @@
 #!/bin/sh
-echo "Error: ng-annotate has not been built. Execute ng-annotate/build/build.sh and retry."
+echo "Error: ng-annotate has not been built.\nRetry after doing this: cd <ng-annotate-path>; npm install; cd build; ./build.sh"
 exit 1

build/es5/ng-annotate-main.js

@@ -1,2 +1,2 @@
-console.error("Error: ng-annotate has not been built. Execute ng-annotate/build/build.sh and retry.");
+console.error("Error: ng-annotate has not been built.\nRetry after doing this: cd <ng-annotate-path>; npm install; cd build; ./build.sh");
 process.exit(1)